Revealed: Enzo Maresca's masterplan to hold out with 10 men against Arsenal - Chelsea's half-time tactical shift that learned from past mistakes, why Pedro Neto swapped wings and how he justified hooking Estevao Willian

We were waiting to see whether Anthony Taylor was being sent to his pitchside monitor to take a look at Moises Caicedo’s challenge on Mikel Merino when an almighty yell emerged from the Arsenal bench. They had already watched it back on their own iPads and, well, weren’t happy.

Mikel Arteta’s assistants Albert Stuivenberg and Gabriel Heinze led the complaints committee with fourth official Sam Barrott. Set-piece specialist Nicolas Jover performed VAR hand signals towards Taylor. Even Kepa Arrizabalaga, Arsenal’s back-up goalkeeper formerly of Chelsea, went over for a word with Barrott while a few other analysts also voiced their anger.

They were in a tizzy. But Chelsea? They were calm by comparison. Enzo Maresca looked towards his own set-piece coach Bernardo Cueva, who sits at the back of their bench with his own iPad. Cueva flashed back a face that suggested, yes, a red card is probably coming.

Maresca consulted his assistants, including Willy Caballero and Danny Walker, to discuss who to bring on and who to sacrifice in light of losing a midfield general in Caicedo. The consensus? Don’t change the side. Keep it as is. Get to half-time then tweak.

This was Chelsea’s sixth dismissal of the season in all competitions – seventh if we throw in Maresca’s for celebrating their late win over Liverpool in October – and so, granted, they have had plenty of practice in playing games with 10 men. But the reaction to Caicedo’s red against Arsenal was brave from Maresca, positive, and entirely different from what we expected after previous experiences.

Manchester United away – Robert Sanchez red card after five minutes. They had to make at least one change to bring on second-choice goalkeeper Filip Jorgensen. But Maresca declined to stop there. He made not one but two immediate substitutions, sacrificing both of his wingers to bring on Jorgensen and a defender in Tosin Adarabioyo. It reeked of negativity, left Chelsea without any attacking impetus, and United won 2-1.

Brighton at home – Trevoh Chalobah red card after 53 minutes. Maresca immediately brought on a defender in Josh Acheampong for a midfielder in Andrey Santos, and then, less than 10 minutes later, another defender in Malo Gusto for a winger in Estevao Willian. Negative again, Chelsea were leading 1-0, but Brighton went on to win 3-1.

The reds they received in fixtures thereafter came too late to make substantial changes. Joao Pedro against Benfica – 90th minute. Gusto at Nottingham Forest – 87th minute. Liam Delap at Wolves – 86th minute. They were already winning in those and held on.

But this time, Caicedo’s badly-timed challenge left Chelsea a man shy after 38 minutes. Truth be told, those of us in the press box expected the same old story might unfold – a knee-jerk substitution, a desire to go on the defensive and a defeat, this time to the league leaders. 

Instead, Chelsea stood still until the interval. When the half-time whistle was blown, Maresca bolted down the tunnel with his fellow coaches in tow. 

Like many managers, Maresca has a whiteboard with magnets in the changing room – 11 in red and 11 in blue. Well, 10 in blue this time. While waiting for the players led by Reece James to trickle in, Maresca was rearranging those figures in conversation with Caballero, Walker et al.

Maresca told Estevao he was being replaced by Alejandro Garnacho, and then explained why to the entire group. 

The easy move would have been to sacrifice an attacker for a midfielder to fill that Caicedo-shaped hole, but no, they had the initiative and wanted to hold on to it.

It was a like-for-like replacement – a winger for a winger – but it was needed for how they were going to approach the remainder of this game. 

It was not a slight on Estevao that he was the one hooked. Until Caicedo’s red, Gusto had been galloping down the right-hand side to overlap the 18-year-old Brazilian to allow him to move inside into central positions and closer to Joao Pedro.

Now, that would no longer be happening, certainly not as regularly as it was when it was 11 v 11.

Maresca wanted Gusto to lessen his flying forward because they could no longer afford to have their back four turning into a back three, and he swapped Pedro Neto from the left wing to the right because the 25-year-old Portuguese is his most relentless runner. 

A starter in every single Premier League game this season and their fastest player, he would be willing to fulfil his defensive duties while still offering a threat on the counter-attack.

Garnacho was brought on to give them that width over on the left instead as he tried to stay high and wide when not needed to help Marc Cucurella. Garnacho was also told to stay high and wait for those beautifully pinged diagonal balls from James to come his way. 

Maresca told Enzo Fernandez to drop deeper into the midfield rather than acting as their No 10. He told Joao Pedro, later replaced by Delap, to try to remain towards the top of the pitch to avoid this game turning into attack versus defence. 

He told the team to push up when they could – indeed, Chelsea's average positions show their backline played deeper in the first half than the second – and in a final few words of encouragement, he asked them to 'double the effort'.

Chelsea were meaner than Arsenal, more composed, and, in terms of Maresca’s tactics, braver. They took the lead through Chalobah and only conceded the equaliser once Bukayo Saka finally escaped the clutches of Cucurella to cross for Merino to head home.

Maresca will hope his side are not forced to compete with 10 men again any time soon, but if nothing else, Chelsea have at least shown they now know how to handle it.