Atletico Madrid are off to a curiously slow start. It’s the rare year where there might be some cracks at the top of La Liga. The departure of Cristiano Ronaldo from Real Madrid means there’s a crack of daylight at the top of the table. But, three games in, the perennial favorites, Barcelona, and Ronaldo-less Madrid are perfect and Diego Simeone’s team has already dropped five points. Is there anything amiss with Atletico, or have their opening three games been the kind of fluke that the next 35 games will make everybody forget? The most notable difference for Atleti so far this season, is that their defense simply hasn’t been up to their usual standards. Last year they were the best team in the league defensively. They only conceded 0.87 expected goals per game, one of only two teams, along with Getafe, under the one goal barrier. This year, they’re at 1.21. That’s a really big jump. It’s easy to see that the defense has performed relatively poorly, getting under the hood and figuring out why is important for figuring out whether it will continue. Traditionally Atleti have been happy to cede territory in their opponents half, but been extraordinarily aggressive in their own. Here’s what their defensive heat map looked like last season. This year, well, so far that pressure map looks entirely different. There are lots of reasons that might be. They’ve played an interesting set of opponents, going away to Valencia and drawing, before beating Rayo Vallecano at home and then going on the road (and playing 20 minutes down a man) to lose 2-0 to Celta Vigo. It’s certainly possible that some combination of tactical interplay is what’s driving the difference. It’s also possible that Simeone is playing catch-up when it comes to indoctrinating parts of his new team defensively. Here are the players that led the team in ball pressures per 90 minutes last season (and played over 900 minutes). It’s a peculiar system that Simeone runs. The team doesn’t press high up the field, but still asks the forwards and wingers do to a lot of defensive work, dropping into their own half and then harassing the ball. Often times one or both wingers are asked to pinch inside and serve as an extra midfielder while one of the forwards drops back to cover the wing. It’s how Simone can both nominally play a 4-4-2 system while also seeming to have bodies everywhere behind the ball. Several of the players who were instrumental to that system are now gone. Four of the team’s ten most active players at pressuring the ball are no longer around. For the attackers that’s not a huge change. Kevin Gameiro, and Fernando Torres were both bench options by the end of last season, and Yannick Carrasco left last January for China, but in midfield, the loss of Gabi looms large. Yes, he was 35, and his legs weren’t what they were, but his expertise at holding the midfield together was real. In three games so far this season, Simeone has deployed three different midfield pairings. Against Valencia, Koke and Saul Niguez started together. Against Rayo, Koke sat and Rodri came into the side to pair with Saul, and then during the debacle against Celta it was Saul and Thomas Partey. Three matches, three different partners for Saul. It’s possible Simeone is planning to mix and match all season long, customizing his midfield approach to his opponents. It’s also possible that he simply doesn’t know what his best midfield is yet. World Cup summers are short, and they cast long preparation shadows. Simeone is trying to work newcomers like Rodri and Thomas Lemar into the side. He is trying to do it despite Lemar, along with both starting forwards in Antoine Griezmann and Diego Costa, as well as Koke and Saul being gone for most of the summer on international duty. It’s certainly possible that the first three weeks are simply a symptom of everybody not quite knowing each other yet and a team that needs to work its way up to full speed. But, Simeone needs to get them there, because the defense simply isn’t working as well as it’s supposed to. They’re conceding both more shots, and better shots than last year. Last year they conceded 11.87 shots per game and 0.08 expected goals per shot and this year that’s up to 12.33 and 0.10. The fact that both numbers have gone up suggests that rather than seeing a style change, we’re simply seeing a defense that isn’t executing at the high levels we’re accustomed to seeing from Simeone teams. Atletico’s style also gives them a smaller margin for error. Their grind it out defensive approach means that often times even beating mediocre teams means lots of work. Last season, even while finishing second the team was ninth in expected goals scored per game with only 1.18. They only took 10.95 shots per game, only five teams took fewer. Even at the best of times Atletico make things difficult for themselves. Of course, if anybody deserves the world’s faith when it comes to molding and shaping a defensive unit, it’s Simeone. He has repeatedly worked with shifting personnel to put together teams that dominate on the defensive side of the ball. There was a time when the midfield was patrolled by Gabi and Tiago. He managed to navigate Diego Costa leaving and then returning. This is a team that managed to move on from once talismanic winger Arda Turan seamlessly. Simeone has managed the same thing in the defensive line where Diego Godin is the only constant. Miranda left, Filipe Luis left and came back. Toby Alderweireld came and went. A cadre of young defenders took their places with Lucas Hernandez and Stefan Savic in particular stepping to the fore. Simeone is the constant on the sideline, the majority of the players on the pitch have changed over the years. Atletico will probably be fine. Simeone will take the new pieces, integrate with the old ones, and put together a strong squad that will finish comfortably in the top four of La Liga. That doesn’t mean there’s nothing wrong at Atletico right now. There is. It just means that given his track record Simeone is almost certainly the man to put it all right, and to do it quickly.