One massive trade created one massive paradigm shift from the East to the West.

Erik Karlsson's arrival in San Jose made the Sharks the defensive team to beat. And with the two-time Norris Trophy winner having left the Senators, that blue line is pretty barren. The Western Conference is projected to be a meat grinder in 2018-19, and the top five defensive teams in our rankings all come from the West.

Here's how we rank the defensive groups for all 31 NHL teams entering the 2018-19 season. The criteria included overall depth, strength of the team's top pairing, last season's output and a general sense of how the pieces fit.

This group would have already been high on the list, headlined by Brent Burns and the perpetually underrated Marc-Edouard Vlasic. Add two-time Norris winner Erik Karlsson? No team boasts a more talented trio. Vlasic, a true shutdown defenseman, has typically been paired with Justin Braun, but Karlsson's arrival creates a shuffle. Vlasic should start the season alongside Karlsson -- the thought alone will give opponents fits. As long as Karlsson stays beyond this season, the Sharks are set for some time. Twenty-five-year-old Joakim Ryan, who has played well alongside Burns, is still on his entry-level contract; he's an RFA next summer.

A model in depth, any player among the Predators' top four (P.K. Subban, Roman Josi, Ryan Ellis and Mattias Ekholm) might profile as a No. 1 on another team. Ellis is in for the long haul after signing an eight-year, $50 million extension that kicks in next season. That contract might turn out to be a bargain. GM David Poile only added fuel with a shrewd free-agency signing of Dan Hamhuis (two years, $2.5 million). Although Hamhuis turns 36 in December, don't see this as a nostalgia tour for the returning Pred. Hamhuis has proven that he can still log 20-plus minutes per night, though those minutes might be managed on the third pairing.

When you think of the Jets' D, you often think of the big, physical Dustin Byfuglien, one of the league's best. But their other top defenders are sneakily elite: Jacob Trouba, Josh Morrissey and Tyler Myers. Morrissey signed a bridge deal (two years, $6.3 million) shortly before the season. The expectation is that the 23-year-old will continue to improve and cash in big time once that deal expires -- whether that's with the Jets remains to be seen. Trouba and Myers are both due for new contracts next summer. Although the group looks terrific right now, it's going to take some finagling for GM Kevin Cheveldayoff to keep the band together.

Of course the Kings' defensive identity is best associated with its stud No. 1, Drew Doughty. But there's balance behind him, too. This is a team that surrendered a league-low 203 goals last season. Jake Muzzin never seems to get enough credit. Alec Martinez, 31, wasn't at his finest last season -- though he logged a career-high 22:51 in ice time per night -- but has the capacity to rebound. Youngsters Daniel Brickley (a highly coveted college unrestricted free agent from Minnesota State) and Derek Forbort (the 15th overall pick in 2010) have potential to develop into stars.

The Wild defense seems to have it all. A trusty veteran who can shoulder a yeoman's load? Check: Ryan Suter played nearly 27 minutes per night last season. Blueliners who can put up big offensive numbers? Definite check: Three of the Wild's top 10 point scorers last season, Suter, Matt Dumba and Jared Spurgeon, were defensemen. Suter's return from an ankle injury is of the utmost importance. We saw how Minnesota crumbled without its star defenseman in the playoffs. Meanwhile, new GM Paul Fenton picked up where Chuck Fletcher left off, putting faith into Dumba as the face of the future. Dumba signed a five-year, $30 million deal this summer, which is smart by the team; if the 23-year-old had inked a bridge deal, he surely would have commanded more two or three years from now.

Dan Girardi, who was bought out by the New York Rangers last season, isn't a liability -- as long as he's paired with Victor Hedman. Speaking of the towering Swede, you need little reminding that Hedman is among the league's elite blueliners, after he finally won his first Norris Trophy last season. Ryan McDonagh and Anton Stralman are as steady as you'd hope for in veteran middle-pairing D-men, and Mikhail Sergachev is only trending up. Unfortunately, Braydon Coburn's best hockey is behind him. Tampa Bay made waves in the preseason when it terminated Jake Dotchin's contract due to the 24-year-old's reporting to camp out of shape (expect his camp to file a grievance).

The top pairing (Hampus Lindholm and Josh Manson) is above league average. Lindholm -- 24 years old and locked in through 2020-21 at a reasonable rate of just above $5 million per season -- boasts a terrific, rounded-out game. The real strength here comes in the second pair of Cam Fowler and Brandon Montour. With so many questions lingering about the Ducks' aging core, it should be noted that the defense is immune. All key blueliners are 26 or younger. This group would be higher if not for dependability issues at No. 5 and 6.

This defense underwent a big facelift this offseason, and we have to say, we love the new look. Calvin de Haan and Dougie Hamilton elevate what was already a talented young core. Hamilton should slide into the first pairing, alongside Jacob Slavin. De Haan, meanwhile, is a good left-handed partner for Justin Faulk on the second pairing. Expect Faulk's name to keep circulating in trade rumors; he was a prime candidate to be moved this summer, and it doesn't seem that the situation has totally settled. Depending on the emergence of Brett Pesce, this group might be even higher by season's end.

It's incredibly encouraging that T.J. Brodie will reunite with Mark Giordano. That is a terrific top pairing, and Giordano brings out Brodie's best. (The duo split after Dougie Hamilton's arrival in 2015 but rekindle their chemistry in one of the great NHL love stories of 2018-19). Noah Hanifin and Travis Hamonic are an average second pairing, but there's a serious drop after that. Hanifin, by the way, gets a totally clean slate after his trade from the Hurricanes. The 21-year-old inked a six-year, $29.7 million deal with his new team, which should age well.

Seth Jones and Zach Werenski, the Blue Jackets' sensational top pairing, catapult Columbus high on this list. In ESPN's second annual Now & Later Rankings, one respondent picked Jones as the best player in the league four years from now; Jones was the only defenseman named in that poll. GM Jarmo Kekalainen parted with veterans Ian Cole and Jack Johnson to create more opportunity for other exciting youngsters, such as the ascending Markus Nutivaara. A now-healthy Gabriel Carlsson could be a secret weapon.

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So much of the Penguins' defensive success hinges on Kris Letang. Assuming the No. 1 has a bounce-back season, this defensive group has a decent middle class; otherwise, players might be slotted in roles a bit too big for them. We're not projecting huge things from Jack Johnson, though Pittsburgh is renowned as a place for players -- especially defensemen -- to revive their careers. Johnson should partner with Justin Schultz to start the season, though we wouldn't be surprised if coach Mike Sullivan shuffles around his bottom pairings early on.

St. Louis returns its entire defensive group, which ranked sixth in the NHL, allowing just 2.71 goals per game. The Blues are mighty fine on the right-hand side, with Alex Pietrangelo flanked by Colton Parayko on the second pairing. This group will only get better as 21-year-old Vince Dunn gets even more NHL experience; he was a pleasant surprise in 2017-18, playing 75 games. Jordan Schmaltz signed a two-way contract this September, which means he could spend some time in the AHL. However, the 2012 first-round pick has potential to plug in right away or later as injuries strike.

John Carlson is a true No. 1, and he can make any partner look terrific. Lately, that has been Michal Kempny, who arrived from the Blackhawks last season via a trade and revived his career. (Thinking about returning to Europe, Kempny is now a top-pairing defensemen for the Stanley Cup champions). The middle two (Matt Niskanen and Dmitry Orlov) for the Capitals are very good, but behind them it's a bit dreary. The pairing of Christian Djoos and Brooks Orpik does not inspire confidence. Washington has great defensive depth in its prospect system, though those players are being stunted by a logjam.

It's a funky group, with plenty of different skill sets (look no further than the top-line pairing of Charlie McAvoy and Zdeno Chara). McAvoy had spells of brilliance as a rookie, though his season was hampered by health issues. Most importantly, he showed that he has the capacity to shoulder huge minutes. Chara, who turns 42 this season, is entering the final year of his contract but should sign a palatable extension. That a player such as Torey Krug is a second-pairing guy is a huge boon. John Moore's five-year deal remains a curious signing, if only for the term.

Although Oliver Ekman-Larsson highlights the top pairing, the drop-off from his duo to the third pairing is pretty minimal. The biggest problem here is an imbalance with too many left-handed shots. The Coyotes are easing Jakob Chychrun back slowly as he returns from knee surgery. In the meantime, either Jordan Oesterle, who played last season with the Blackhawks, or Ilya Lyubushkin, a KHL signee, might slot in for the open sixth spot.

This is a perplexing group to figure out right now. Of course there's Shayne Gostisbehere and Ivan Provorov, who are ascending talents. Gostisbehere dropped off a bit last season but has tremendous upside. Provorov, who is just 21, might be one of the most underrated defensemen in the league. He's an RFA next summer and is due for a huge payday. There's some early injury concern and questions as to whether reinforcements are needed.

If Toronto has a weakness, it's the defense. But the group isn't as shabby as many think. The Maple Leafs don't have the strongest top pairing, but Morgan Rielly is consistent. A healthy Nikita Zaitsev might do wonders. And forget about the Game 7 meltdown; Jake Gardiner is a left-handed defenseman who sometimes has defensive lapses but possesses tremendous puck-moving ability (let's not forget, he put up 52 points last season). Nonetheless, this could be Gardiner's last go in Toronto, as he's an unrestricted free agent next summer.

Brent Seabrook and Duncan Keith aren't what they once were, but they're still better than most (especially Keith). Seabrook's decline was troubling, but most are distracted by his bloated contract, which didn't age well. The club's first-rounder in 2017, Henri Jokiharju, is a player to be excited about and could dazzle in his rookie campaign -- or undergo a few growing pains. Playing with Keith will help. Behind those three is a logjam of average defensemen fighting for minutes. Connor Murphy's early-season absence (back injury) isn't ideal but isn't going to make or break this blue line. 2018 first-round pick Adam Boqvist has impressed enough in camp that he might start the season with the big club.

Nobody profiles as a true No. 1, but nobody really stands out as a negative, either. The early-season suspension of Nate Schmidt for violating the league's substance abuse policy is a dagger. He led all Vegas defensemen in ice time, playing 24:15 per game in the Golden Knights' playoff run. The Schmidt-less top four (Brayden McNabb, Colin Miller, Shea Theodore and Deryk Engelland) are all serviceable, if unexciting. Theodore -- the team's second-best defenseman last season -- has the biggest upside, but the RFA has spent the summer in a contract standoff with the team. The No. 5 and No. 6 will be weak links, but the Theodore and Schmidt absences have paved the way for 24-year-old Jake Bischoff or 19-year-old Erik Brannstrom to see valuable time this preseason.

Although Florida significantly upgraded its top-six talent this summer with the Mike Hoffman acquisition, GM Dale Tallon did nothing to address the defense, which allowed 34.6 shots per game last season, the third-worst mark in the league. Last season's top pairing of Keith Yandle and Aaron Ekblad is about as middle-of-the road as you'll find, though they will start the season split apart. The talent slowly drops off after that, but there are decent prospects waiting to break through. It's a good thing new captain Aleksander Barkov is proficient in his own end.

This blue line isn't as thin as it was last season, but it was small steps more than total improvement. Samuel Girard is a compelling talent that simply needs more experience. Pairing Girard with veteran Erik Johnson will help. Tyson Barrie (coming off a career-high 57 points) and Nikita Zadorov (entering his sixth NHL season but still improving) combine for the second pairing. Ian Cole adds a much-needed veteran presence and should partner with Patrik Nemeth for a shutdown third line.

Dallas is mediocre. It has an elite offensive defenseman in John Klingberg and a top-tier prospect in Miro Heiskanen, but other than that, there's not much to write home about. Of course, had the Stars been the ones to orchestrate a trade for Erik Karlsson, this would be a different story (though that might have cost them Heiskanen). Dan Hamhuis, who anchored the second pairing last season, signed with Nashville. Roman Polak is the uninspiring free-agent replacement. New coach Jim Montgomery is known for his dynamic college offenses, and it's unclear how his style will translate to this group.

This defense can't be as bad as it was last season (33.4 shots/3.2 goals per game), right? The Oilers don't have a true No. 1 -- or No. 2 or No. 3 -- but they have decent middle depth as long as those players stay healthy. Oscar Klefbom, Adam Larsson, Darnell Nurse and Kris Russell are the only real locks here. Veteran Jason Garrison, buried last season in Vegas, was worth a flier but doesn't appear to be the answer. Same with Jakub Jerabek. The best bet might be turning to the future with top draft pick Evan Bouchard.

24. New York Rangers

New York's best defenseman, Kevin Shattenkirk, is coming off a serious knee injury. Marc Staal is a shell of his best self. Through the preseason, he appears to have recovered from knee surgery just fine, but the dynamics of the team around him have changed significantly since he signed a four-year contract in the summer of 2017. Neal Pionk and Brady Skjei showed exciting flashes (Pionk last season, Skjei the season before) but still need to find consistency. The team traded for Adam McQuaid to supplement an unexciting bottom.

Even with a Rasmus Dahlin bump, this is one of the league's most pedestrian defensive groups. It's great that Rasmus Ristolainen has overachieved the past two seasons, but there's a reason he has had to shoulder so many minutes. Through training camp, Lawrence Pilut -- voted the Swedish Hockey League's top defenseman last season -- has been a pleasant surprise, and even if he isn't on the roster to begin the season, he could see time later. Ditto for Brendan Guhle.

Defense was the Devils' Achilles' heel in 2017-18. Captain Andy Greene is one of several weak links. There were plenty of jobs up for grabs at training camp, which speaks volumes about where this blue line is. The biggest loss of the offseason was John Moore, who signed in Boston. He might be replaced by Egor Iakovlev, a KHL import, or Ty Smith, the Devils' first-round draft pick in 2018. Smith is talented enough to make the opening night roster. It's just a matter of how the Devils want to manage him.

This is a rough-looking group without Shea Weber. And even if Weber is healthy, there isn't much to be excited about. Carey Price is wasting prime years with a patchwork blue line in front of him. Jeff Petry stepped up in Weber's absence with offensive production (career highs with 12 goals and 42 points). Last summer's Karl Alzner signing (a whopping five years with a $4.625 average annual value) didn't pan out in year one; the stay-at-home defenseman looked especially slow, though he brings the benefit of serving as a mentor to younger players.

It will probably be another season of growing pains. Ben Hutton, Derrick Pouliot and Troy Stecher could all use seasoning. Hutton, especially, needs to rebound after spiraling from an all-situations defenseman to healthy scratch at the end of the season. When you look at this defensive group, you don't see any playmakers -- and that's a problem. Coach Travis Green said he has made some tweaks to get more offense out of his defense, and that would be welcome, considering that their highest-scoring defenseman last season, Alex Edler, had only 34 points.

The talent here is lackluster. Nick Leddy and Johnny Boychuk are a fine pairing, and they complement each other's skill set, but as the No. 1 duo on the roster? It only gets worse from there. First-round pick Noah Dobson -- a draft day gift that fell into the Islanders' lap -- had slim odds of making the NHL roster, but we would have been much more excited about this team if he got an early try (Dobson returns to his junior team for now). Now for the optimism: New coach Barry Trotz is known for defensive structure. We'll see what he can whip together with this group.

Here's the good news about the Red Wings' defense: There's plenty of room for prospects to audition (likely Dennis Cholowski and/or Libor Sulak). Here's the bad news about the Red Wings' defense: See above. This is probably the last go for 37-year-old Niklas Kronwall, a Stanley Cup stalwart entering the final year of his contract. Mike Green, the only defenseman with notable offensive production, is missing the beginning of the season because of a scary virus attacking his liver.

There's no time to sulk over losing Erik Karlsson -- but there's also no possible way to replace him right now. Dylan DeMelo, one of "the six assets" cited in the team's news release, joins a bland group of defensemen. Thomas Chabot (only 64 games of NHL experience) and Cody Ceci likely inherit the first pairing in Karlsson's absence. Chabot -- 21 and the MVP of the 2017 World Junior Championship in a losing effort for Canada -- is the most promising Ottawa blueliner and could quarterback the power play.