The Blues lost 2-1 at Old Trafford as first-half goals from Bruno Fernandes and Casemiro were enough to ease the pressure on Ruben Amorim.

That pressure has now been transferred to Maresca, who's been criticised for his reaction to Robert Sanchez's early red card, which saw him take off Estevao for goalkeeper Filip Jorgensen and swap out Pedro Neto for Tosin Adarabioyo, before Cole Palmer's niggle forced him off for Andrey Santos.

Explaining his decisions, Maresca said: "The reason why we changed Pedro and Estevao was because they attack with the five players always.

"And we defend with the four, and we can defend with the four when we are 11 vs 11, but 11 against 10, I think we need to defend with the width, so we decided to go with the back-five, this is the reason why.

"And then the other one, Garna, he was ready to go on, but then Wes(ley Fofana) asked for the change, because he was tired after a long time, so we changed and we decided to go for Tyrique (George), and the idea was to give Garnacho minutes."

Asked if the crowd's negative reaction to Garnacho warming up had any impact, Maresca insisted: "No, no, no. He was ready, I sent him for the warm up and he was ready but then Wes asked for the change so we decided to go with Malo."

Danny Murphy told BBC's Match of the Day that he thought Maresca's substitutions were "really negative".

"I think bringing an extra defending on is understandable and taking off an attacker, but a few minutes later Palmer is off after they're 1-0 down," he said.

"We felt Neto and Cole Palmer coming off was a really negative move. Okay, we trust his word that he (Palmer) is struggling a bit with injury but maybe he should've brought him off at the beginning and left Neto on for his pace.

"Because even when they got level men second half, they really didn't have that much of a threat on the break, to beat somebody, there was only Joao Pedro who really had that forward-thinking mentality."

Wayne Rooney also believes Chelsea lacked "urgency" even after United had Casemiro sent off at the end of the first half.

"They had all the imagination on the pitch and I felt that is what was missing for Chelsea," Rooney said.

"They had a lot of possession going side to side second half but they missed that creativity which Neto or Cole Palmer could bring them.

"I think the change was strange but thankfully it helped United.

"It was a strange game, I think when it went to 10 men apiece, I just felt there was no urgency from Chelsea to try and get back in the game.

"Obviously they get one goal back from a cross, there were no crosses in the box, the two crosses in the box they get one goal and then they have another good chance.

"It was just slow, side to side, yeah the weather was poor but I think if you're a Chelsea fan you want to see them with a bit more urgency to try to get something from the game."

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