One of the most impressive victories in the UEFA Champions League this week was Arsenal's 4-0 win against Atlético de Madrid.
It was a contest which caught the attention of the UEFA game insights unit for several reasons, notably the way Arsenal overpowered Atleti with a four-goal spree between the 57th and 70th minutes, and the set-piece quality that yielded two of those goals.
As it happened: Arsenal 4-0 Atleti
Atleti's defensive control
Before focusing on those aspects of Arsenal's performance, Atleti warrant a mention for the challenge they presented their hosts with their compact, deep defence. They were hard to break down in the first period when, as the video clips show, they shut down space centrally, shifting within a low block and looking to force Arsenal sideways or out wide.
Champions League tactical insight: Atleti flexibility
As displayed in the video above, there was flexibility in Atleti's formation, which shifted between a 4-4-2 and a 5-3-2. In the view of UEFA Technical Observer Pål Arne Johansen, a key figure in that respect was right-winger Giuliano Simeone, who dropped into the back line when Myles Lewis-Skelly, Arsenal's left-back, got into forward positions and did the same when protecting the box from crosses from the other flank (as did left-winger Nicolás González with balls from the right side).
From a coaching point of view, Johansen added that if there was fluidity in Atleti's tactical shape, their identity does not change. "A key element of their identity is, and has for many years been, defensive control," he explained. "If you are Simeone, defensive control is a priority – and then you have to find the system that gives you that."
This leads to a broader point for coaches: that identity is usually foremost in a coach's training-ground work. Johansen explained: "Actually, you only train with two possible purposes. Number one, you train to strengthen your own identity and the possible variations within that. And then, you train to sharpen what you're specifically going to do to maximise the chances of winning your next game."
Arsenal seize the supremacy
As the graphic illustrates, Atleti's defensive work limited Arsenal to a first-half xG (Expected Goals) total of 0.51. The second half was a different story, with Gabriel's breakthrough strike sparking a flurry of goals.
"Once we've opened the game up, we could generate more space and chances to hurt them," said Arsenal coach Mikel Arteta, and the video below shows his side in full flow.
Champions League tactical insight: Arsenal penetration
The second period brought more forward passing, more one vs ones and more penetration from Arsenal. The video above begins with them creating an opening through a lovely piece of skill from Martín Zubimendi. As for clip two, this features a tactical detail that Johansen highlighted as significant, namely that there were more – and quicker – rotations from Arsenal in the second half, which helped get the deep midfielder on the ball.
In this case, crucially, it led to Lewis-Skelly carrying the ball up the pitch to set up Gabriel Martinelli's goal. "You see Lewis-Skelly on the second goal: he comes inside and changes position with Declan Rice and that created a degree of confusion," observed Johansen.
For his part, Arteta praised Lewis-Skelly for the way "he carries the ball, the way he attracts players, and the ability he has to release the ball in the right moment".
As an aside, Arsenal's goal flurry continued an early scoring pattern noted by UEFA's game insights unit so far in this league phase. Of the 200 goals so far, 32 of them have been followed by another within five minutes – 19 times by the team that had just scored, 13 by the team which had conceded. Is the explanation more psychological than tactical? It is a question we will come back to as the season progresses.
"The ones who get the headers are specialists and the ones taking them are specialists, and their coaching staff work on them very well, for sure. They have an incredible value in every match."
Atleti's Diego Simeone praises Arsenal's set plays
Gunners thrive on dead balls
"The dead ball is one of those [tools] against a block that is so compact, so organised," said Arteta after Tuesday's match. "We think it's a situation we can exploit. We looked for it and were very effective."
They certainly were – and, for Arsenal, it is nothing new. They were the joint-third top scorers from set plays in last season's competition with five goals, and their two dead-ball goals against Atleti, featured in this third video, emphasised once more the threat they pose.
Champions League tactical insight: Arsenal set pieces
The first clip shows the corner routine that brought their fourth goal. With Atleti marking man to man, look at the movement from a cluster of red shirts to pull defenders across and create space at the back post. Martinelli played a crucial role in blocking the man marking Gabriel, enabling him to have a free header.
The second clip, meanwhile, displays Gabriel's opening goal and is notable for another excellent delivery from Rice and multiple deep runs.
In the section below, Davide Ancelotti – who prepared Real Madrid's set pieces when coaching at the Santiago Bernabéu alongside his father Carlo – will reflect on his approach to set plays. Their importance is considerable in his view and explains why clubs like Arsenal employ a set-piece coach (in their case, Nicolas Jover). "Set plays are massive," said Ancelotti, now coach of Botafogo in Brazil. "The numbers show it. And having a specialist can help you a lot."
Coaching reflections: Davide Ancelotti on training set plays
"First, you have to establish a culture and make your players believe that set plays are important. I talk about it first and ask the players how many times they've won or lost a game because of a set play, as the first thing is to convey the message that offensive set plays can win you games.
"Then I look to understand the attitude and aptitude that each player has in the box and establish functions for them. As well as your set-piece taker, you have to talk to them and establish which kind of player can have the attitude to be a blocker, to be a runner, to be 'alive' on the edge of the box and to be the safety for the counterattack.
"You have to invest time on set plays and you have to be consistent. I like to do it in almost every training session, but in small doses – it could be ten minutes. I work almost every day in the first part of the session, normally after the warm-up. I like to do it at the beginning of the session when they are more focused.
"I can divide the team into groups and make two different drills and one might be set plays. In terms of session design, it might only be a small group of players, or it could be three teams, with one team that only defends and the other two that attack. Or I could do it in a real game situation, 11 against 11. It always depends on which day it is in the week.
"Regarding the physicality of the sessions, you have to manage the load. Whether you work with or without 'opposition', and whether you play with a lot of second balls and leave them to play on after the set play, these are considerations related to how far you are from the game and the load of the session.
"As for the role of video, we always record and then show the players – with videos in the gym or in the canteen – what we do in the session. They always have videos of our offensive set plays: how we do them in training and how we do them in games.
"Of course, the review of the games is really important because you always find things that you have to improve, and also, if you if they see that you're creating dangerous situations, then they start to believe. As I said at the beginning, you start to create a culture because, in the end, it always comes down to them being convinced about what they're doing."
"I do it in different ways – it can be without opposition, with 'semi' opposition or with complete opposition against a 'sparring' team. Or also in the form of a competition with two teams that attack the same 'sparring' team."
Davide Ancelotti on his set-piece sessions