The World Cup has been full of surprises. Of the five teams rated most likely to win the World Cup before the tournament by FiveThirtyEight’s Soccer Power Index, only France won its first match. Spain, Argentina and Brazil could manage only draws, and worse yet, Germany lost to Mexico. While Spain’s 3-3 draw against Portugal can be excused — Cristiano Ronaldo’s team is rated the eighth-best side in the tournament and has legitimate hopes of winning the whole thing — the other three face larger problems.

Germany’s difficulty may be the most acute. While Argentina and Brazil saw their chances of reaching the knockout round go down only slightly (77 percent to 68 percent for Argentina and 89 percent to 85 percent for Brazil), Germany is suddenly at risk of being the third consecutive defending World Cup champion to go out in the group stages. Die Mannschaft’s odds of reaching the round of 16 plummeted from 90 percent to 64 percent.

Germany can’t say the loss was undeserved. Mexico created more expected goals, a statistical estimate of the quality of scoring chances, than Germany did, with the Mexican counterattack ripping up the German defense even when it did not create shots. Eight times in the match, Mexican players combined to move the ball straight through midfield — with more than 50 percent of ball movement directly toward the goal — and into the German penalty area. Though only four of those ended in shots, one produced a goal.

That Hirving Lozano game-winning goal was the most devastating example of this counterattack. It starts with an open-play turnover, leading to a few quick passes and runs, a couple of defenders beaten on the dribble and a pass into the penalty area. The map below shows the Lozano goal and three other moves like it. If Mexico had been more clinical in creating good shots from these moves, the result could have been even worse for Germany.

So what can Germany do? Only with better counterpressing from the forward line and midfield — to prevent opponents from striding through the center of the pitch with ease as Mexico did — can Germany regain its defensive strength. Coach Joachim Low started only two central midfielders, Toni Kroos and Sami Khedira, in order to get playmakers Mesut Ozil and Thomas Muller into the lineup behind a central striker. A personnel shift that adds another central midfielder to the mix while dropping an advanced creator seems like the obvious next step. Of course, this isn’t as easy as just scribbling a new name on the lineup sheet. Player positions and relationships will have to be reconsidered and restructured. Mexico exposed Low’s first lineup, and now he needs to identify a backup plan and get his players ready to go with it in just a few days. The task is great.

A similar tactical problem looms for Argentina. While La Albiceleste did not see its chance of advancing go down by a large margin, it was in trouble from the moment it was placed in a group full of such capable defensive sides as Croatia, Iceland and Nigeria. With a 32 percent chance of being eliminated before the knockouts, Argentina should be worried.

And what went wrong against Iceland does not seem easy to solve. Argentina attempted 26 shots against Iceland but generated only about 1.1 expected goals, a rate of about 0.04 expected goals per shot. The only teams in the tournament that have created lower-quality shooting chances are Saudi Arabia and Tunisia.

You would expect a team with Lionel Messi to be creating good scoring chances. But Argentina has a problem: Messi is tasked with bringing the ball forward from defense to attack. If Messi must pick up the ball in deep areas, who will make the pass or run near the penalty area to break open the defense? According to the statistical company Impect, which tracks whether passes took a team beyond an opposition defensive player, Argentina’s passes only bypassed a defender 23 times, the fourth-fewest of any team in the World Cup through the first four days.

At the same time, Iceland created about 0.9 expected goals on eight shot attempts, a rate of 0.11 expected goals per shot, showing that Iceland was able to create good scoring opportunities despite Argentina’s conservative approach. If Argentina’s defense can be exploited like this, it’s hard to suggest that coach Jorge Sampaoli should bring on a more attack-minded midfielder like Ever Banega and risk opening up further at the back. A counterpress could also work, but Argentina already tried that. Sampaoli drilled his players to press high up the field and seek to create turnovers that could give them new possession in advanced areas, but the team’s middling results and underlying numbers from qualifying suggest that has not worked either. It may be that the only real solution is hoping that Messi puts together a truly legendary tournament and covers both creative roles, advancing the ball through the midfield and beating the defenders.

By contrast, Brazil’s exceptionally talented roster should not have to depend on one player. But against Switzerland, it did. Although its goal came from a brilliant individual finish by Philippe Coutinho, in general, Brazil tried to ride Neymar to victory. The creative winger was constantly on the ball and, more than that, constantly tasked with beating a man to create space for the attack to move forward. Eighteen times Neymar was involved in a one-on-one with a defender. This is high even for Neymar, who averaged about 10 one-on-ones per match for Paris Saint-Germain. But while Neymar was successful about 60 percent of the time in the French league, here he struggled, winning only five of 18 contests. Switzerland consistently bodied and often fouled Neymar, leaving him unable to progress the ball as he usually does.

And while that could just be a fluky bad game from Neymar, Brazil has reason to worry. The draw against Switzerland was Neymar’s first match back from injury, and before the game, Brazilian coach Tite said Neymar was not fully fit. Brazil struggled to break down Switzerland because, time and again, its attack waited for Neymar to beat a defender, and he couldn’t do it.

Unlike Argentina, however, Brazil already has the players to lean on while Neymar works himself back into shape. Coutinho and Marcelo are elite passers, while Willian adds about 3.5 complete dribbles per 90 minutes, 12th highest among players in the big five leagues with at least 2000 minutes played. None of them alone can do what Neymar usually does, but Brazil’s starting lineup as a collective can carry some of Neymar’s workload. What will be required for Brazil, rather, is that the team rebalance the attacking load until its superstar is fully fit. Brazil has the talent to continue to roll without Neymar at 100 percent, if it can limit his responsibilities.

All of these teams remain favored to escape their groups. But a shocking early exit is possible for Germany and Argentina if they cannot solve some major problems. Brazil should be able to continue and succeed without Neymar at his best, at least for a while. But to reach or win the final, all three teams must make important changes.

Check out our latest World Cup predictions.