The United States women's national team enters the Olympics as reigning World Cup champions and gold medalists. If they capture gold in Rio, they'll be the first team ever to become Olympic champions one year after lifting the women's World Cup. More so than any other World Cup winner in history, they'll be expected to do so.

Somehow, the USWNT is better now than they were in Canada just one year ago. Instead of entering the Olympics as one of three big favorites, alongside France and Germany, they're the very clear front runner, and anything less than gold will be a disappointment.

In 2015, the USWNT was a team in transition. They'd just made a coaching change 18 months prior, and head coach Jill Ellis didn't even start to figure out her best team until their quarterfinal win against China. This time around, she had a plan for a new shape, a more possession-oriented style of play and the integration of young talent to replace aging (and retiring) stars.

If you haven't followed the U.S. women since their big triumph in Vancouver last year, here's everything you need to know before the women's soccer tournament at the Olympics gets underway on August 3.

Mallory Pugh, Crystal Dunn and Lindsey Horan are here to melt your face off

Even if she doesn't crack the starting lineup, the player you're likely to hear the most about is 18-year-old winger Mallory Pugh. She's never played in a college or professional club game before, but she's already one of the most dangerous wingers in the world. Pugh scored on her debut against Ireland this January and has added two more goals since. This one, against Costa Rica, is her best.

The last player left off the World Cup squad was Crystal Dunn, who's played all over the pitch but has settled into a right wing role for club and country. Former USWNT manager Tom Sermanni used to play her at right back. Despite being a great coach and a great person, Sermanni should never be forgiven for this atrocity.

While mostly playing up top for the Washington Spirit in 2015, Dunn scored 15 goals, winning the NWSL Golden Boot and MVP awards. This year, she's become more of a playmaker than a goal-scorer for her club, but she has 10 goals for the USWNT in 2016. Here's an absolute rocket that she scored against England.

Dunn and Pugh, as good as they may be, are not locks to start. It's likely that only one of them takes the pitch if long-time star (and current NWSL MVP race frontrunner) Tobin Heath is fit. If Megan Rapinoe is completely healthy as well, it's possible that they both sit. But we know we're going to see Lindsey Horan, who's taken over from the retired Lauren Holiday in the center of midfield.

Horan is just 22, and she used to be a striker. Her scoring record was spectacular at Paris Saint-Germain, but she's been converted to midfield since coming home, playing in the same position for both her country and the Portland Thorns. Stylistically and functionally, she's very similar to Carli Lloyd -- Horan doesn't have the silky touch and tricks you'd expect from an attacking central midfielder, but she's creative, physical, and scores a lot of goals.

So while Horan is the woman slotted into Holiday's old position, she's hardly playing the same role as Holiday, one of the most technically sound players ever to wear a USWNT shirt. That's fine, since other players like Pugh, Dunn, Rapinoe, Heath, Morgan Brian, Christen Press and Alex Morgan bring plenty of finesse to the table. What the USWNT needed was an Abby Wambach replacement, even if that player wasn't a striker. Horan fills that role perfectly by arriving late in the box and hurling herself at the ball with no regard for her safety or the safety of her opponents. She is a wrecking ball.

We need to talk more about Pugh

It's very difficult to talk about Mallory Pugh honestly because of America's history with failed wonderkids. We are very weary of overhyping young players.

But any hedging on Pugh's ability or future is inherently disingenuous. There are times when she not only looks faster, more creative and more energetic than her established peers, but more intelligent and technically sound as well. There are other teenagers with her pace, and other teenagers with her skill, but none with both. There are maybe only a half-dozen players of any age on earth with comparable vision and decision-making in the final third. This is reflected in her team-leading seven assists for the USWNT in 2016, which she's racked up despite starting fewer games than six other attacking players.

Not to hype Mal Pugh is to be dishonest. She is the best 18-year-old in the world, the best 18-year-old the USWNT has ever had, and she's worthy of starting for any team in the world.

The right back battle between Kelley O'Hara and Ali Krieger

Long-time starting right back Ali Krieger appears to be a backup going into Rio. Kelley O'Hara, who has been the primary backup at both fullback positions under Ellis, has now been thrust into a starting role. Krieger is a true fullback, while O'Hara has played more winger than defender over the course of her career. Ellis has made the decision to go with a better attacking player at right back at the expense of defensive solidity. Importantly, starting left back Meghan Klingenberg is also better going forward and worse defensively than Krieger.

Making comparisons between men's and women's soccer is generally a bad idea, but this particular one is useful. In the mid-2000s, men's teams became enamored with attacking fullbacks and started converting wingers to play the role, shifting away from balanced true fullbacks like Paolo Maldini and Gary Neville. The model player was Dani Alves, Barcelona's right back. It took the better part of a decade, but a lot of teams eventually realized that this was a very bad idea as their opponents effectively counter-attacked into the space that attacking fullbacks vacated. Now, a lot of men's teams that dabbled in AlvesMania are shifting back toward traditional fullbacks or experimenting with back three formations that allow Alves-like wingbacks to bomb forward while providing better defensive cover.

Alves' role worked for Barcelona because Barcelona and Alves were both the greatest ever at what they did. Alves was a true superstar talent and provided enough going forward for the risk Barca was taking to be worth it. They also had so much possession and were so good at pressing to break up counter-attacks that their weakness was rarely exposed. The current USWNT is in a similar situation.

While the U.S. women don't have quite the possession stats that the Barca men did in those days, they still have a lot of the ball. Horan and Lloyd are equally effective at pressing high when the ball is lost to prevent opponents from countering quickly. And in the event the USWNT's opponent is able to create a two-on-two counter attack in a lot of space, the central defense pairing of Julie Johnston and Becky Sauerbrunn almost never gets beaten. Given all of that, it makes sense for Ellis to take a risk with two very attacking fullbacks, and that's why you're likely to see O'Hara starting instead of Krieger.

But is the greatest defense we've ever seen still on that level?

So, about Sauerbrunn and Johnston, and goalkeeper Hope Solo behind them. There are some cracks in the armor. They're probably still the best group of center backs and goalkeeper in the world, and any team would be happy to have them, but none of the three is in her best form. All three have turned in at least one genuinely poor performance in NWSL this season. And given how dominant they were at the World Cup, duplicating their outrageous World Cup seems nearly impossible. No one has ever defended that well for two tournaments in a row.

The USWNT has 13 clean sheets in 2016, but the games where they did allow goals were a bit concerning. One of them was a wild 3-3 draw against Japan, featuring a calamitous 93rd minute equalizer from the 10-woman Nadeshiko. The other was against Germany, when they conceded this goal to Anja Mittag.

This isn't a goal that the USWNT would have conceded at the World Cup. One of Johnston or Sauerbrunn would have put pressure on the ball while the other one would have covered the space behind. Solo wouldn't have let that shot trickle in at her near post either.

Ultimately, this is nit-picking. There is nothing "wrong" with the USWNT center backs and goalkeeper; they are good enough to win an Olympic gold medal. But if Ellis is going to play a hyper-aggressive style that concedes counter-attacks in space multiple times per game, she's counting on her center backs and goalkeeper to be exceptional, not just very good.

Morgan Brian's fitness problems create a question in front of that defense

Everything changed for the USWNT at the World Cup when suspensions forced Brian into a starting role. Her ball-retention skills and positional sense were a revelation for the Americans, who wouldn't have gone on to lift the World Cup without her.

Since then, when Brian's been at her best, she's been even better than she was in Canada. With Ellis switching from a 4-4-2 (or something closer to it than anything else we can put in numbered formation notation) to a 4-3-3, Brian has taken up a deep-lying playmaker role behind Horan and Lloyd. With her in the team, the USWNT is extremely difficult to win possession from, but Brian's been suffering from hamstring injuries and hasn't been her best in two months.

Brian's backup is Allie Long, a great but much different player. Long is a true destroyer who wins the ball regularly with crunching tackles, something Brian can't claim to do. But Long is also nowhere near the distributor that Brian is, and she's also not as good at moving into the right spaces to receive the ball. With Long in the game instead of Brian, much of the distribution duties fall on the central defenders, and the USWNT gives the ball away more often.

While Long might be better than Brian defensively, that doesn't matter if Brian's absence means opponents have more opportunities to attack. There's no better defense than possession, and because of that, Brian is just as critical to the American defense as the players behind her are.

Alex Morgan is back to her best

At the World Cup, Morgan scored just once. She wasn't at full fitness entering the tournament and started to look like herself only at the very end. Since then, she's improved dramatically and has been one of the team's best players this year. She has only two goals in NWSL, but she's been very unlucky. She's sixth in shots and was second in expected goals when USWNT players left NWSL for Olympics camp.

Finally caught up (not including last night's games) with @NWSL xG scores: As expected, @Jess_Mac14 pulling away pic.twitter.com/wsOQE4EFNo — Chad Murphy (@Soccermetric) July 10, 2016

Morgan's four goals on the victory tour and 10 for the Americans in 2016 suggest that she's fit and worthy of being the starting striker again. She's also improved her movement off the ball and hold-up play significantly, eliminating the need for her to have a strike partner. And that leads to...

The changing role of Carli Lloyd

As a midfielder in a two-woman center, Lloyd was often ineffective. While Lloyd is undoubtedly one of the world's top players, that role accentuated her weaknesses -- positioning and turnovers. She was rarely in the right place to stop a counter-attack, and her middle-third turnovers led to dangerous counters for opponents. When Brian was introduced to the lineup and Lloyd was moved to striker, those weaknesses stopped being significant problems, and Lloyd turned in the performances that helped her win the Ballon d'Or.

But there was something missing from Lloyd's game at striker as well. While it masked her deficiencies, it also didn't allow her to do much of two things she's really good at -- winning the ball high up the pitch and arriving late into the box. With Morgan no longer needing a partner up top to perform at her best and Ellis switching to a three-woman midfield, Lloyd gets to play her best position as the most advanced player in a midfield three. Her positional issues and turnovers are never punitive, but the team gets to make use of her ball-winning ability and late runs as well. Lloyd is finally playing the role she should have been playing all along.

A bench full of wonderful options

Last year, it felt like the USWNT had good players on the bench but lacked the capacity to change games in a meaningful way. Now, their 18-woman Olympics roster feels deeper than the 23-woman one they took to the World Cup.

Long and Brian are two very different styles of defensive midfielder, and they can even play together if need be. If Ellis wants to bring a possession player on for Lloyd, she has Press and Rapinoe ready. Press also presents a more direct option than the starting wingers and is a like-for-like backup to Morgan. If a more physical striker is required, Horan can move up top while someone else comes into midfield. Krieger can come off the bench to solidify the defense, while O'Hara can move up the pitch and play as a defensive winger. Only two of Pugh, Dunn and Heath can start, so the third will be a terrifying attacking substitute.

No matter the situation or tactical goal, Ellis will have someone on the bench to achieve what she wants.

This tournament is different because expectations are different

There were no real expectations for last year's USWNT. They were coming off a coaching change and carrying veteran players who fans didn't feel had earned their spots on the squad. Johnston was an emerging talent, not one of the top center backs in the world. Lloyd was out of form. Morgan was hurt. Wambach looked like a ball and chain fastened to the squad. The midfield was a mess. They won the World Cup anyway.

A year later, the USWNT has everything -- youth, experience, pace, creativity, technique, power, finishing, a solid midfield and a settled defense. The reigning world champions have improved dramatically in just one year. Anything less than a gold medal will be a huge disappointment. They are the clear No. 1 team in the world, and opponents will see them as such.

So is the USWNT ready to face a Germany team with a healthy Dzsenifer Marozsán? She's one of the best players in the world, but she wasn't fit for last year's World Cup semifinal. Are they ready for a France team that will play a conservative, keepaway style? It's unlikely that Les Bleus are going to take risks and leave the Americans a lot of space to attack into. Are they ready for a Brazil team with a rowdy home crowd and motivated Marta? Brazilian female footballers have struggled for respect in their country and will see this tournament as an opportunity to earn it for good.

The USWNT is the best team in the world, but their opponents are fierce and prepared for what the Americans will throw at them. This tournament might end up being more exciting than the World Cup.