This is where it gets serious. The little fish – your Maribors, your Liverpools, your Ludogoretss – have had their moments, have enjoyed the attention, have been roundly patronized by the press all over Europe ... and have been sent on their way with a cheery wave. Now, it's time for the big fish (and Basel) to step up. Swim up. Whatever fish do.

16 teams are left in the Champions League, and all of them have the ability to make life awkward for their opponents. Of those, at least eight will consider themselves in with a shot of lifting the cup in early June, which by the standards of modern football is a decent proportion. A couple of those will certainly be eliminated, which given the bloodthirstiness of today's television audiences is ideal.

16 teams, eight fixtures. All come with their own interest and intrigue and all should be well worth watching; there's something for every taste, from Basel-Porto for the hipsters to Real Madrid-Schalke for the sadists. But if you held a gun to SB Nation Soccer's head and forced us to pick our absolute favorites, we think there are three that have the potential to be stone-cold classics, and between them scratch every possible itch.

There's Juventus and Borussia Dortmund, two teams who could not be having more different seasons at home, meeting in a fixture that simply drips with nineties nostalgia. By contrast, the high-powered oligarch-off between Chelsea and Paris Saint-Germain is as quintessential a fixture as modern football has to offer; two glitzy projects clashing in a competition both will be hoping to win. And there's always at least one big Premier League side with a nightmare draw: here, Manchester City have to contest with Barcelona, who have rather inconveniently overcome their minor crisis, decided not to sell Lionel Messi, and started scoring goals again.

More than that, though, more than the specifics of the draw, there's the sense of occasion. Whether the hysterical carnival of modern football raises your hackles or widens your eyes, the Champions League, as a spectacle, gets everything right. There's the anthem and the pageantry; the giant wobbly parachute and the Gazprom. There's English co-commentators rolling their eyes to the heavens and asking, apparently without irony, "What do these fifth officials even do?" There's Messi and Ronaldo chasing one another past record after record.

And, at the end, underneath everything disposable and ridiculous, there's the irresistible pull of elite, knockout football under floodlights, one of the finest sights that this dying planet has to offer. You've missed it. We've missed it. This is where it gets serious.

vs Paris Saint-Germain Leg 1: Feb. 17, 2:45pm ET (Paris) Chelsea Leg 2: Mar. 11, 3:45pm ET (London) Users The Teams

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Key Players contract Key Matchup PSG Paris Saint-Germain held on to all of their key players from last year's team and even managed to add David Luiz, but it still doesn't seem like they've quite cracked Europe's elite. The Parisians are involved in an incredibly tight three-way title race in Ligue 1 and now, due to their failure to overcome Barcelona and win their group, have to face Chelsea. They're yet to look significantly improved from last season – but then again, last season's team was mere minutes away from beating Chelsea, eventually only being eliminated in the quarterfinals on away goals. Chelsea Chelsea were solid but unspectacular when José Mourinho returned to the helm last season, but they've made great strides in the short time since. The Blues are cruising atop the Premier League, and only Manchester City seem to have a (small) chance of toppling them. New signings Diego Costa and Cesc Fàbregas have blended in perfectly, and unlike last season, star defensive midfielder Nemanja Matić isn't cup-tied. Add that to the small fact that they have one of the best managers in the history of the game, and it's clear they're serious contenders. PSG Paris Saint-Germain were only able to manage a draw in their group opener at Ajax, so many didn't expect much when they hosted Barcelona in the next game. But PSG gave us a thrilling 3-2 victory, and gave themselves hope for overhauling the Blaugrana to take first. But a loss the Camp Nou on the final matchday allowed Barcelona to walk away with the top spot. A greater worry, however, might be the way PSG struggled against APOEL – their difficulties in recording two 1-0 victories suggests they still haven't figured out how to make the most of their immense talent. Chelsea With Chelsea demolishing everyone domestically, it came as a bit of a surprise that they struggled at times in the Champions League. And by "struggled," we mean the Blues emerged unbeaten, boasting 14 points and a +14 goal difference, helped along by their 6-0 win over Maribor and their 5-0 victory at Schalke. Yet both those sides were also able to record a 1-1 draw with Chelsea, so it's clear that José Mourinho's side is not invulnerable. Zlatan Ibrahimovic At age 33, and with Edinson Cavani in the team, Zlatan Ibrahimović probably shouldn't be PSG's most important player. But the team has been built around him to such an extent that the Parisians often forget how to play when he's out of the game. He's equal parts target man and playmaker, and perhaps the finest striker with his back to goal on the planet. He has 93 goals over 113 appearances in a PSG shirt, but his hold-up play and passing are just as big a part of a game as his goal-scoring. His space and touches could be limited against Chelsea, so he'll have to make the most of the opportunities he does have. Nemanja Matic Chelsea have enough attacking depth to remain dangerous even if one of their stars goes down. Nemanja Matić, however, is irreplaceable. Cesc Fàbregas' dodgy defending, Kurt Zouma's inexperience and John Terry's lack of pace are all regularly masked by Matić's positioning, athleticism and crunching tackles in the center of the pitch. The Blues didn't have him in Champions League last season, but his presence may be the biggest reason they're being touted as favorites this time around. Eden Hazard vs. PSG's right back Eden Hazard's dribbling skills and off-the-ball movement are some of the best in the world, and he's nigh-on impossible to track. That'll leave Gregory van der Wiel, who's started each of PSG's Champions League matches at right back, with his hands full. Deciding when to close him down or when to back off; when to stay home or when to follow him into the center of the pitch will not be easy for the Dutch international. Hazard is an expert at twisting opposition defenses and slicing straight through them with clinical passes, meaning van der Wiel will be under constant pressure to position himself perfectly at all times.

vs Shakhtar Donetsk Leg 1: Feb. 17, 2:45pm ET (Lviv) Bayern Munich Leg 2: Mar. 11, 3:45pm ET (Munich) Users The Teams

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Key Players contract Key Matchup Shakhtar Shakhtar Donetsk are a major power in the Ukrainian Premier League, winning five straight league titles and a stunning eight out of the last ten. They’ve also made their mark on the Champions League with a few impressive performances in recent years. However, this season has been more of a struggle; whether it's due to the distractions of domestic unrest or losses of key players, Shakhtar just haven't had quite the same edge as normal. They had to scrape and claw their way to a second place finish in their group, and now their reward is to face the footballing Godzilla that is Bayern Munich. Talk about a tough hill to climb. Bayern Munich Bayern Munich started off the second half of the season with a shocking loss and a hard-fought draw, yet the biggest club in Germany still looks destined to win a third straight Bundesliga title. Pep Guardiola's team is a juggernaut, with an incredibly deep squad that boasts star-level talent at every position. Beating them will require a top-shelf performance with focus, discipline, and more than a little luck. They seem bound for the final; the question is whether or not someone else can shock them – and the rest of the world – along the way. Shakhtar Shakhtar's struggle for form definitely followed them from their domestic league into Europe. When they played BATE Borisov, they looked like world beaters, earning massive 7-0 and 5-0 victories. But Shakhtar had a far harder time against Porto and Athletic Bilbao, drawing twice with the Portuguese side and earning just a point against Bilbao. They rarely looked the least bit convincing, and in absence of a miracle it's nearly impossible to imagine them progressing. Bayern Munich Bayern were almost perfect on their march through the group stage, with the only blemish a last-minute 3-2 defeat to Manchester City in England. They had no real problems with CSKA in Moscow, and won their three home games without conceding a single goal. As if that isn’t already frightening enough for Shakhtar, the highlight of Bayern’s group stage performances came when they pounded Roma into the dirt, going to the Italian capital and coming away with a 7-1 win. Alex Teixeira With eight goals between the Champions League and the Ukrainian Premier League, Alex Teixeira has been Shakhtar's steadiest goalscorer since the end of Oleksandr Gladky's early season goal glut. His skill and dynamism has given fits to many a defense since he arrived in Ukraine five years ago, and Shakhtar coach Mircea Lucescu should be proud for the work he's done developing Teixeira as a player. Now, the Brazilian attacker will be afforded a chance to show the world the kind of force he's become. Thomas Müller Even with the incredible amount of talent that Bayern have assembled in attack and midfield, it's still Thomas Müller at the heart of it all. He's been virtually ever-present for Bayern this season, starting all but five of Bayern's matches and scoring 13 goals in all competitions. His versatility and energy allow Pep Guardiola to keep plugging him into the lineup in a variety of places, filling in for injured players or those who need rest without worrying about a dropoff in performance. That's an incredible luxury for a manager to have. Pep Guardiola vs. Mircea Lucescu Perhaps it's a little obvious to pit the managers against each other, yet it's still worth noting this particular matchup. Pep Guardiola is widely regarded as one of the most brilliant managers around, but Mirca Lucescu is no slouch at the job himself. Neither man is perfect, though – both managers have a nasty tendency to out-think themselves, spinning down into a hole and dragging their clubs along with them. Sometimes they get too cute or clever with a tactic and find themselves exposed, sometimes they get cocky with a particular lineup and get punched in the mouth for it. If Guardiola and Lucescu just stick to the script and go with what got them here, this could be an exciting and quality tie. If one or both of them lose the plot, it could get awfully one-sided or even just plain weird – but possibly in a good way. Frankly, it's hard to know whether we should be rooting for normalcy or insanity.

vs Schalke Leg 1: Feb. 18, 2:45pm ET (Gelsenkirchen) Real Madrid Leg 2: Mar. 10, 3:45pm ET (Madrid) Users The Teams

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Key Players contract Key Matchup Schalke Schalke are a club that excels at performance art. The miraculous, amazing and incredible flow freely in Gelsenkirchen; but so does the shocking, disappointing and absurd. Much of the time, they are a good club that plays wonderful football, but the Royal Blues are also capable of the most spectacular collapses. Led by Klaas-Jan Huntelaar and Eric Maxim Choupo-Moting up top, Schalke can be devastating in front of goal and solid in their defense, but it can also fall apart so quickly. Confident they might appear, but one goal against could lead to them conceding six or seven in their Champions League tie. Real Madrid Ah, the Champions. The ten-time winners. Yes, the Merengues had no trouble with the group stage, breezing through with six wins, 16 goals scored and just two conceded. Needless to say, that was the best showing of any top team, which is little surprise considering they have Cristiano Ronaldo, Gareth Bale, James Rodríguez, Karim Benzema and Luka Modrić all in one squad. Madrid have shown themselves to have a couple of issues at the back, but you’d never know it from their Champions League performances. Are they still the best team on the continent? Perhaps, but that doesn’t mean they’ll get a free ride to the winner’s podium. Schalke Things started brilliantly for Schalke, who drew Chelsea 1-1 at Stamford Bridge to open the group stage. Then they returned home and drew lowly Maribor 1-1. That about sums up the nature of Schalke. The Royal Blues then split matches against Sporting Lisbon, putting them in precarious position heading into the final two matchdays. A 5-0 loss to Chelsea had them on the verge of going out, but they rescued their campaign with a win over Maribor to send them through to the Round of 16, where we can see what absurdities they have up their sleeve once more. Real Madrid Real Madrid got drawn with Liverpool, Basel and Ludogorets. That’s hardly the Group of Death, but it’s not a total farce. And yet the Merengues walked away with six wins in six matches, scoring 16 goals and while giving up just two. Cristiano Ronaldo and Karim Benzema combined for 10 goals as they laid waste to every team that came in front of them and put away any concerns that maybe they would struggle to handle their overabundance of attacking talent. Dennis Aogo Schalke know they can be dangerous in front of goal, with Klaas-Jan Huntelaar and Eric Maxim Choupo-Moting. They also know they are going to be vulnerable at the back, even if Roberto Di Matteo has given them a needed bit of discipline. The question is what happens in the middle: how can they support both the defense and the attack? That means all eyes will be on Dennis Aogo. He's going to be the deepest midfielder, tasked with shielding the back line, while also initiating the transitions so the forwards can get the ball in space. That's asking a lot, but that's what happens when you're forced to face the Galácticos attack. Whoever plays goalkeeper Real Madrid are going to score goals. Even if Luka Modrić won't be available for both legs, they’re still going to out-skill Schalke in the midfield. And as shaky as their defense can be (especially in the absence of Sergio Ramos), it’s not as if Raphaël Varane and Pepe aren’t capable of brilliance. But what about in goal? The Merengues have real questions at goalkeeper, and whether they choose to go with Iker Casillas or Keylor Navas, no one will have total confidence in the man between the sticks. Both have been error-prone, and neither has taken ownership of the starting spot. Whoever takes the gloves is the one player who could throw this tie away for Real Madrid. Cristiano Ronaldo vs. Atsuto Uchida Playing against Cristiano Ronaldo is never easy. Nor is being a wingback in a 3-5-2. Atsuto Uchida is going to have to do both in the same match. Schalke need him to get forward or Eric Maxim Choupo-Moting will have to drift out wide and then he's not a threat in front of goal anymore. But Uchida also can't get stuck up front and let Ronaldo run wild. If he doesn't get back, Ronaldo will spend the entire match running at Roman Neustädter, which is a disaster waiting to happen. It's pretty much inevitable that Ronaldo is going to make an impact, but can Uchida at least keep him somewhat in check so he doesn't win the tie single-handedly?

vs Basel Leg 1: Feb. 18, 2:45pm ET (Basel) Porto Leg 2: Mar. 10, 3:45pm ET (Porto) Users The Teams

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Key Players contract Key Matchup Basel Basel have dominated the Swiss Super League in recent years, winning the last five titles. Their position as the unquestionably biggest and richest team in the country has afforded them the luxury of experimenting with young talents from around the world, and they’ve become something of a stop-off for young players to showcase their talents before moving on to bigger things. However, that’s not to discount their own excellent youth system; Ivan Rakitić, Xherdan Shaqiri and Granit Xhaka are among the names to have emerged from their academy in recent times. They’re certainly not serious Champions League contenders, but they’re young, fun, and more than capable of pulling off an upset. Porto Porto are two-time winners of the Champions League (albeit with the first coming in 1987 when it went by its more tactful title of the European Cup), and are the last continental non-powerhouse to have lifted the trophy, having swept aside Monaco 3-0 over a decade ago. Alas, the days of José Mourinho have long since passed, and with them have gone Porto’s hopes of winning the world’s biggest club competition again. They’re certainly not a bad team, and head into their round of 16 clash with Basel as favorites, but it’s unlikely we’ll see them again once the quarterfinals are out. Basel Basel’s road to the knockout stages was a rocky one, though that was to be expected in a group that contained both Real Madrid and Liverpool. A 5-1 drubbing away at the former didn't exactly set the tone, but Basel were able to pick themselves up, rebounding with a stunning victory at home to the latter. Three points from their subsequent three games against Madrid and minnows Ludogorets meant they headed into the final matchday at Anfield needing a draw to progress. It was nervy, but they clung on at 1-1 to advance at the expense of their hosts. Porto Porto had one of the most straightforward runs to the knockout stages, benefiting from the absence of any tournament contenders. They didn't lose a single game, beating Athletic Club and BATE both home and away, and drawing both fixtures with Shakhtar Donetsk. They scored a fierce 16 goals en route to winning the group; five of them netted by star striker Jackson Martínez. Their successful passage earned them what is, on paper, the easiest knockout stage draw they could've had, but Basel look more than capable of providing an upset. Shkëlzen Gashi Albanian international Shkëlzen Gashi earned himself a move to Basel last year on the back of an excellent season at their domestic rivals Grasshopper, and the 26-year-old is proving to be worth every Swiss franc they paid. He's netted 13 times over the first half of this domestic season – no mean feat considering he’s nominally a left winger – and is proving his 19-goal campaign at his previous club was no fluke. In Paulo Sousa’s system he loves to dart inside from his wide position, dazzling defenders with his diagonal runs and feeding off the crisp passing of his midfield teammates. If Porto can keep him quiet, they’ll have a much easier task. Jackson Martínez There is no doubt that the star of this Porto team is striker Jackson Martínez, whose importance in Julen Lopetegui’s starting lineup cannot be overstated. The 28-year-old Colombian is the only player in their squad to have started every single one of their league games so far this season, and in those 21 games he’s scored a typically impressive 16 goals. Big, quick and utterly lethal in front of goal, Martínez is the complete package, and he’ll be looking to make his mark in what could be his final season before departing for a bigger club. Yacine Brahimi vs. Basel’s right-back Jackson Martínez tends to steal the headlines for Porto, but his teammate Yacine Brahimi has shone since arriving from Granada in the summer. Usually deployed on the left of Julen Lopetegui’s attacking trident, the Algerian international loves to drift into pockets of space in the center of the pitch – a position from where he is a big goalscoring threat. He scored four in the group stages, and Basel’s right-back, be it the aggressive Philipp Degen or the versatile Taulant Xhaka, may find it difficult to stop him adding to his impressive tally.

vs Manchester City Leg 1: Feb. 24, 2:45pm ET (Manchester) Barcelona Leg 2: Mar. 18, 3:45pm ET (Barcelona) Users The Teams

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Key Players contract Key Matchup Manchester City In yet another flashback to last season, Manchester City are once again paired with Barcelona in the Round of 16. That’s bad news for the Abu Dhabi Group, who’ve made no secret that their goal is to come away with a Champions League trophy. Last season was the first time they progressed past the group stage, only to fall – rather embarrassingly – to Barcelona. And despite massive investments made since 2008, Manchester City have managed just two Premier League titles. While there's no denying their talent, their recent domestic struggles include getting booted from the FA Cup by Middlesbrough, which can’t have fans optimistic of their chances of beating Barça. Barcelona Barcelona failed to reach the semifinal stage of the Champions League last season for the first time since 2007, eliminated by eventual runner-up Atlético Madrid. In fact, they failed to win any major trophy, completing what was a tumultuous and ultimately disappointing season for the Blaugrana. Despite some mid-season struggles, Barça now appear to be playing some of their best football of the season at just the right time. With the lethal trio of Lionel Messi, Neymar and Luis Suárez leading the attack, it's difficult to imagine that Barcelona won't be able to make a deep run in the knockout stages. Manchester City After four match days, Manchester City’s hopes of earning a place in the knockout round were on life support. City had managed just two points, but thanks to some equally poor performances from CSKA Moscow and Roma, they still had a shot. Sergio Agüero’s stoppage time winner against Bayern Munich on matchday five kept them alive, and a final day victory over Roma ensured that City completed the great escape, finishing second in Group E. It was an impressive turnaround, but they’re going to have to put on a much better showing to advance to the quarterfinals for the first time. Barcelona Drawn in a group with Paris Saint-Germain, Ajax and APOEL, there was never any real doubt that Barcelona were going to go through to the knockout rounds. But after falling to PSG 3-2 in the second group stage game, Barça’s ability to lead the group was called into question. The top spot wasn’t decided until the final match, when Barcelona and PSG met again. This time, a 3-1 victory – featuring goals from Lionel Messi, Neymar and Luis Suárez – ensured both a Barça victory and their standing atop the group. Yaya Toure Yaya Touré. Or, indeed, the absence of Yaya Touré, because the midfielder, fresh from the Ivory Coast's Africa Cup of Nations win, is suspended for the first leg. Judging by the performances of Manchester City over the past month, Touré remains the glue that holds this side together. Sure, the team will be relying on Sergio Agüero to score the goals, but it’ll be the Ivorian tasked with trying to keep Barcelona from keeping absurd amounts of possession. He’ll need to disrupt the midfield in the reverse fixture, keeping Barcelona from putting City’s defense under constant pressure. Lionel Messi Until Lionel Messi retires or suffers a sudden and shocking loss of ability, he’s always going to be the most important player for Barcelona. This season, he leads the team in both goals and assists, and is a constant nightmare for opposing defenses. The massively improved form of Neymar, and the addition of Luis Suárez, have helped make Messi even more dangerous – a truly frightening thought for Manchester City. Vincent Kompany, Eliaquim Mangala and Martín Demichelis vs. Barcelona’s attack Manchester City have yet to face an attack able to score goals with as much proficiency as Barcelona, yet their defense has still consistently leaked them. There’s every reason to believe that City, too, will be able to score, but Barcelona’s three-pronged attack will almost certainly be able to score more. So whatever combination of central defenders Manuel Pellegrini chooses to start will have the responsibility of trying to keep Luis Suárez, Neymar and Lionel Messi contained. It’s easy to put on paper, but with Vincent Kompany looking like a shadow of his last-season self and the rest of the back line rarely looking world-class, you have to think this matchup could be rather one-sided.

vs Juventus Leg 1: Feb. 24, 2:45pm ET (Turin) Borussia Dortmund Leg 2: Mar. 18, 3:45pm ET (Dortmund) Users The Teams

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Key Players contract Key Matchup Juventus Juventus are undoubtedly the dominant team in Italy at present, though that probably says as much about the sad state of affairs on the peninsula as it does about the Old Lady. They’ve cruised to their domestic title three seasons running, despite – with the significant exception of wonderkid midfielder Paul Pogba – having a set of pretty average players. This season they were expected to struggle a little after coach Antonio Conte resigned and was replaced by former Milan managerial flop Massimiliano Allegri, but they’re still cruising at the top of the Serie A table. Their comparatively weak squad means it’s unlikely domestic success will translate into continental triumph, and it’d be surprising if they progressed much further. Borussia Dortmund Only three years ago ago Borussia Dortmund were Bundesliga winners; only two years ago they were Champions League finalists. However, this season, manager Jürgen Klopp has seen his bubble burst, with bad sales, bad signings and bad luck leaving BVB struggling near the foot of the table with over half of the season gone. It has been one of the most dramatic declines in recent footballing memory, rendered all the more peculiar by their relatively normal performances in Europe. They cruised through the group stages, looking their spritely, free-scoring selves. If they turn up in similar form against Juventus, they should progress, but if they turn up in Bundesliga mode, they could be in trouble. Juventus Juventus had a much less convincing group stage campaign than their opponents, ultimately finishing just a point above third-placed side Olympiacos. They managed to beat Swedish minnows Malmö both home and away, though away defeats to the Greek champions and to eventual group winners Atlético Madrid left them sitting nervously on the brink of elimination. However, Allegri rallied his troops to a narrow 3-2 win in the reverse Olympiacos fixture, and a goalless draw against Atléti on the final matchday ensured their passage into the knockout stages. Borussia Dortmund Borussia Dortmund managed to put their domestic woes aside in the group stages, finishing top once again – albeit only by virtue of goal difference. They won the first four of their six group games, starting off with a 2-0 win over Arsenal and dispatching bottom club Galatasaray home and away, scoring a combined total of eight goals along the way. They then slipped up in their final two games, losing 2-0 away to runners-up Arsenal and then getting caught in a draw to the Europa League-bound Anderlecht. Paul Pogba Paul Pogba is living, breathing, marauding, goalscoring proof that even the greatest manager in the history of football was fallible. Sir Alex Ferguson let Pogba leave Manchester United for nothing back in the summer of 2012, and has been suffering a growing humiliation ever since. For not only has Paul Pogba established himself as one of the best young midfielders in the world, but probably the best midfielder full stop. The 21-year-old is an incredible all-rounder, whose attacking exploits are only more notable than his defensive ones by virtue of the celebration that tends to follow them. He is a remarkable player, and easily the shining star of an unspectacular Juventus team. Mats Hummels Borussia Dortmund’s star man is center-back Mats Hummels, who was key in Germany’s World Cup success in Brazil last summer. The 26-year-old is widely regarded as one of the best defenders around at present, yet struggling BVB have managed to retain him in the face of interest from some of Europe’s giants. He’s not perfect – former Manchester United boss David Moyes reportedly passed up the chance to sign him because he "couldn't run" – though what Moyes failed to recognize was that what he lacks in pace, he more than makes up for in intelligence. Considering he’ll be going up against Juve’s notoriously slippery striker, Carlos Tevez, that’s just as well. Pierre-Emerick Aubameyang vs. Patrice Evra Borussia Dortmund attacker Pierre-Emerick Aubameyang is one of the few players to have emerged from their horrific first half of their season with his reputation intact. The lightning quick Gabonese winger has established himself as a crucial first-teamer out on the right flank, and will no doubt be relishing this tie against Juve’s ageing left-back Patrice Evra – assuming the injured Kwadwo Asamoah hasn’t made it back from knee surgery in time. Evra certainly isn’t the player he once was, and could well struggle to keep Aubameyang quiet.

vs Bayer Leverkusen Leg 1: Feb. 25, 2:45pm ET (Leverkusen) Atlético Madrid Leg 2: Mar. 17, 3:45pm ET (Madrid) Users The Teams

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Key Players contract Key Matchup Bayer Leverkusen Bayer Leverkusen entered the Champions League as a team expected to attack like crazy, score a lot of goals, and likely advance out of Group C in the top spot. Oddly, they really didn’t do any of those things, struggling to score goals at times on their way to a second place finish behind Monaco. More worryingly, Leverkusen’s league form has also dropped as of late, and if they remain where they are now, in sixth, they’ll miss out on Champions League qualification for the first time since 2012. They remain a dangerous side, capable of breaking down an opponent, but they’ll need to show a more consistent offensive performance if they hope to make a deep run. Then again, they put four past Wolfsburg in their last Bundesliga match, only to lose anyway. Atlético Madrid Last season, Atlético Madrid shocked the football world by not only reaching the Champions League final, but coming within seconds of defeating Real Madrid and lifting the trophy. But then came Sergio Ramos’ late goal, and Los Colchoneros ran out of gas in extra time. So they’re not here as defending champions, but that does little to take away from Atléti’s tremendous run last season. And considering their recent league performances – look past the loss to Celta Vigo, back to their 4-0 dismantling of Real Madrid – there’s no reason for Diego Simeone to believe he can’t take this team to the final once more. And just like a year ago, they’re defensively strong and insanely organized – positive traits for a knockout tournament. Bayer Leverkusen Their fourth place Bundesliga finish last season meant Leverkusen were forced to enter the Champions League during the qualification playoff round. After a close 3-2 win in the first leg against Copenhagen, Leverkusen won 4-0 in the second leg, moving on to the group stage. Despite being drawn into what was viewed as a weaker group, Leverkusen’s offense was twice stymied by Monaco, and they finished one point behind the Ligue 1 side. They came close to missing out of the knockout round all together, but a scoreless draw against Benfica on the final match day, combined with Zenit’s loss, secured their place. Atlético Madrid Not only did Atléti make it to the final last time around, they also surprised by winning La Liga, earning them a spot in the group stages. After being drawn into Group A with Juventus, Olympiacos and Malmö, Los Colchoneros stumbled badly, losing their opening match against Olympiacos, 3-2. The loss proved a wake-up call for the team, and they went on an impressive winning streak with 12 points from four matches, keeping a clean sheet in each one. A scoreless draw in the final matchday against Juve secured first place in the group, and their spot in the Round of 16. Stefan Kießling The 31-year-old striker is starting to show his age, but remains the man up front for Leverkusen. Despite the fact his goal totals are dropping yet again this season – 25 in 2012/13, 15 last season and just 10 so far this year in all competitions – Roger Schmidt continues to rely on him. His experience is likely part of the reason he’s kept his job, but he also likely feels secure because whenever Josip Drmić gets a chance, he can’t seem to find the goal. Leverkusen won’t be able to count on Hakan Çalhanoğlu getting the opportunity for a free kick in a dangerous area, so if they want to advance, Kießling is probably going to have to start knocking a few in. Gabi In the summer transfer window, Atléti lost some vital members of last season's finalists. Diego Costa, Felipe Luis and Thibaut Courtois moved on, but Atléti added talent in their place in the form of Mario Mandžukić, Miguel Ángel Moyà, and Antoine Griezmann. While those men will play a part in whether or not Atléti can match their performance from last season, the one constant through everything has been the team’s captain Gabi. He’s quietly become one of the best midfielders in the world, capable of marking some of the best players out of games, and helping to orchestrate the Atléti midfield. The better Gabi plays, the better Atlético Madrid play. Battle of the midfields Atlético Madrid don’t care that much about possession numbers. If you give them the ball, they’ll take it and gladly try to score, but Diego Simeone doesn’t send his team out with the the goal of taking the ball and keeping it. Thanks to their wonderfully organized system, and every single player understanding exactly what they need to do within said system, Atléti can just clog up the midfield, waiting to take advantage of their opponents’ mistakes. Leverkusen must find a way to win the midfield battle, preferably scoring early and forcing Atléti to push forward and open up their usually tight structure. If the Germans can’t pressure Atléti, allowing Gabi and Tiago to dictate play, it’ll be a long tie.

vs Arsenal Leg 1: Feb. 25, 2:45pm ET (London) Monaco Leg 2: Mar. 17, 3:45pm ET (Monaco) Users The Teams

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Key Players contract Key Matchup Arsenal Arsenal are fighting for fourth place in England and have qualified for the Champions League knockout stages, despite nobody believing they have a chance of winning it. Sound familiar? Alexis Sánchez has made them more dynamic than ever before and they have shown flashes of greatness, but that’s nothing new for the Gunners. It’s hanging with the best teams in Europe that has been their issue. Luckily for them, that won’t be a problem against what still looks to be an average Monaco side – albeit a Monaco side that did manage to win their group against the odds. Monaco Monaco got back into Europe thanks to new ownership that poured money into the club. But when a rather expensive divorce led to cuts in the team’s cash flow, it looked like they’d be done for. Instead, they leaned on their young talent and managed to top their group. They’re finding their form at the right time too, going undefeated since the start of December. Nothing about Monaco has gone as expected, and that’s been to their advantage. But now in the knockout stages, things will get tougher and we’ll find out how good this side really is. Arsenal Once again, Borussia Dortmund got the best of Arsenal in the group stage. Again, the two sides finished level on points, but again the Gunners lost out on goal difference. A collapse against Anderlecht – when they blew a 3-0 lead to finish 3-3 – came back to bite them. Because BVB topped the group once again, Arsenal are forced to take on a winner in the Round of 16, but after Bayern Munich dumped them out at this stage last season, they’ll be thrilled to have been drawn against comparative minnows Monaco. Monaco Monaco were gifted a rather easy group, out of which any of the four might have emerged without surprising anyone. Yet after selling off their brightest talents, most expected Monaco to exit come the end of the round. Instead they lost just once in the group stage, beating Bayer Leverkusen and Zenit, and their incredible defense allowed just one goal in six matches. Their attack left a lot to be desired, scoring just four times, but that was enough to take 11 points and the top spot in Group C. Alexis Sanchez There was a stretch this season when Arsenal were getting killed by injuries and had no form to speak of. They should have crashed, but Alexis Sánchez made sure that they wouldn’t. Their new star is absolutely incredible, single-handedly winning the Gunners a few matches. He gives them a dynamism and unpredictability that breaks up what can be a predictable and plodding attack. Despite not winning their group, the Gunners will be favorites; they won’t need any superhuman efforts, but if anyone is going to give them one, it will be Alexis. Dimitar Berbatov Arsenal are going to have the ball and spend much of the tie on the front foot. If Monaco are going to manage to advance, they’re not only going to need to finish the chances they get, but also manage to create a few chances out of nowhere. That is going to be Dimitar Berbatov’s job. He can be frustrating and bizarre, but there are few players in the world who can be as deadly in front of goal, or turn a seemingly average play into a great chance and score. Monaco are going to depend on him doing just that. João Moutinho vs. Arsenal's holding midfielder Arsenal have had problems deep in the midfield, where Mikel Arteta has been out injured for long stretches of the season. That’s put Mathieu Flamini onto the field more often than Arsène Wenger would like, and the Gunners have even had to turn to youngster Francis Coquelin at times too. João Moutinho pulls the strings in the Monaco attack and will cause the Gunners a lot of problems if he’s able to get on the ball in the attacking third and move forward without pressure. It will fall on Flamini or Coquelin to make sure that doesn’t happen. Credits Lead editor: Kirsten Schlewitz

Editors: Ryan Rosenblatt, Jack Sargeant, Andi Thomas

Authors: Conor Dowley, Ryan Rosenblatt, Jack Sargeant, Andi Thomas, Zach Woosley

Developer: Graham MacAree