Unai Emery knew something had to change from the last time Arsenal met Manchester United. In that encounter, a 3-1 defeat in the FA Cup in January, the manager conceded that his team had played well, but were hit by a counter-punch they were prepared for, yet were unable to stop. “We worked to stop their counter-attack,” he said after the game. “They have very big players to do the transitions and they gave us problems with that.” Romelu Lukaku expanded on that notion too, saying how United looked to exploit the space behind Arsenal’s backline to ensure their victory. “We knew they would leave space for me and Alexis with the full-backs pushing on so it would end up being 3 v 3 or 3 v 2.”

Indeed, this time round, it seemed that with that same approach, and with Manchester United riding high on an improbable Champions League win, they would once again have the measure of Arsenal. Emery’s reaction was not, however, to double-down and go defensive, but to deploy a surprise attacking line-up – at least in personnel terms.

He chose to start with a 3-4-1-2 using Mesut Ozil behind Pierre-Emerick Aubameyang and Alexandre Lacazette whilst Aaron Ramsey got a central midfield berth – and he also opted to play with two natural wing-backs in Ainsley Maitland-Niles and Sead Kolasinac.

Instantly, Arsenal started on the front foot and their goal after 12 minutes was reward for their dominance. Ole Gunnar Solskjaer admitted afterwards that “for the first 15-20 minutes, Manchester United were too slow to get up to Arsenal. We never really put them under pressure, they had time to get that goal.”

It forced United to change their system, moving to match Arsenal, to a 3-4-1-2. Initially, they began with a 4-4-2 but had problems firstly, getting to Arsenal’s two central midfielders because if they pushed up, they left room behind their midfield for Ozil et al. to drop in between-the-lines. The Gunners, in their best moves, tended to play the ball fairly comfortably to Lacazette’s to lay the ball off – as he did for the opener – or drive with it as he did when he won the penalty.

The other issue was that Kolasinac kept on bombing forward, aided by Nacho Monreal’s aggressiveness at left centre-back, therefore Solskjaer asked Ashley Young to drop back into a right-sided centre-back role, and Diego Dalot to wing-back. “We didn’t really change that much, just slight tweaks,” said Solskjaer but it made all the difference as suddenly, United began to dominate. It exposed Arsenal’s top-heavy approach, with the ball being able to get through Arsenal’s first line of press fairly easy. Once it got into midfield, it was almost as if The Gunners were defending with 8 men – therefore to their credit, they did a lot of intense running, as typified by Ramsey who won 8 tackles and covered the most distance in the game at 12.7km.

The front three did eventually attempt funnel back, but in the main, they always looked to get into good counter-attacking positions. In that sense, Emery flipped the script on his Man United because, knowing that they would come to counter-attack, he wanted them to have second thoughts about how they could do it without being left themselves on the break. He wanted to counter the counter-attack. As such, the stretched, end-to-end nature of the game was almost predicted – or wanted – by Emery because he knew Arsenal this time, would have the players back to guard against the counter, and possibly wouldn’t need to attack with so many players. Even if they did, by having the likes of Ramsey and Maitland Niles in the team, it meant that there was enough recovery speed and fitness to win the ball back.

In the end, Arsenal were indebted to saves from Bernd Leno though the real takeaway from the game from the manager’s perspective would be how Arsenal adapted – and have adapted for most of the season – to the change in system, demands. The line-up seemed atypically Emery initially, but in a sense, it was all him. People expect him to be conservative – and certainly, it has come back to bite him in games when he respects the opposition too much – but this XI had all the hallmarks of his normal meticulous approach. The line-up was catered to adjusting to the strengths of his opponents, though, this time he left more on the pitch in terms of exploiting the weakness of Manchester United. It seems as if in the big games, he’s happy to eschew possession too where once at the start of the season, he would attempt to go toe-to-toe with his opponents. As Ramsey said after, “it’s been a season of trying to adapt to certain things Emery wants from us. Sometimes it hasn’t come off, sometimes it has, but it’s a work in process.”

Emery added: “I think we’re improving and also I think we’re being competitive in different matches, away from home and against different teams. We responded and sometimes you’ve seen different systems and different players… We were positive when we were struggling in the table and we took balance in our mind when we were worse – and now after these victories we can be positive, but it won’t change our idea. We need to continue and it will be difficult, and our style and way and thinking will be game by game.”