United were beaten 2-0 at Stamford Bridge and are now 17th in the Premier League after losing a third match in a row.

It is also nine winless games in all competitions for the first time in 38 years and their cause was not helped by the dismissal of Martinez, sent off for two bookings inside two minutes in the second half after Morgan Rogers had given Chelsea the lead.

Martinez, whose outspoken response to a poor summer transfer window earlier in October encapsulated the turmoil engulfing the club, left Carrick facing a losing battle to save the game in west London and perhaps now his job as well.

It remains to be seen whether the 45-year-old will remain in charge for Wednesday’s Champions League game at home to Roma.

“A lot of disappointment,” said Mbeumo. “I thought we played a solid game, a good first half especially.

“And everything was good, the mentality, the work-rate. I think (a win is) going to come.”

Martinez had already been booked for a clumsy foul on Rogers when, at 1-0 down in the second half, he needlessly put a forearm into the throat of Wesley Fofana with a corner drifting harmlessly away.

A second yellow came out, a penalty awarded and Cole Palmer squeezed it past Senne Lammens.

Nevertheless, Mbeumo would not be drawn into singling out the Argentinian for criticism.

“I feel like everyone linked together, even some who made mistakes, we were there for him,” he said. ”When someone did great, everyone was there to get something from this.

“We still trust everyone. With the man down, we still had some frustrations at the end. But I think we have done everything as a team.

“Maybe we just missed some chances. We could have been up early in the game, but that’s a positive to take out of this game.”

The frustration was that United were by far the better team in the first half but missed chance after chance, with Bruno Fernandes – restored to the team and the captaincy after speaking out publicly against his manager – and Amad Diallo the chief culprits.

“The structure was quite good and the mentality,” said Mbeumo. “We had a lack of chances in the last couple of games, whereas we had good ones (on Saturday), so things can still be positive for the next few days.”