An early goal from Marcus Rashford and a deflected strike from Ander Herrera were enough for Mourinho to earn his first victory against Conte's Chelsea at the third attempt.

The Premier League leaders failed to register a shot on target in a Premier League match for the first time since December 2015, and the result means their lead over Tottenham Hotspur is just four points with six games remaining.

"I think they [United] deserved to win because they showed more desire than us, more motivation," Conte said.

"But in this case the fault is mine, because in this case I wasn't able to transfer the right desire, the right motivation to play this type of game.

"To play this type of game from now until the end we must have great enthusiasm, great passion, great motivation to reach this target [of winning the title].

"It's a fantastic target because if we are able to reach it it's a miracle. We must find the right motivation."

Asked whether he was worried by the lacklustre nature of the Chelsea performance, Conte replied: "For sure. I have to be concerned because we have to work together and find quickly the right desire, the right ambition to win this title.

"If someone thinks it's normal for Chelsea to win the title I think this season is not normal, because we started the season as underdogs.

"We stay in a great position but Tottenham is in great form and playing with great enthusiasm. We must find the same."

Chelsea's preparations for the match were disrupted by the absence of Thibaut Courtois due to injury and the hamstring problem that forced Marcos Alonso to withdraw from the starting XI during the warmup, but captain Gary Cahill was in no mood to look for excuses.

Antonio Conte was not pleased by his side's performance at Old Trafford on Sunday.

Asked about Conte's remark that Chelsea's players lacked desire, he replied: "I agree. We expected them to start fast and we had to try and control that, and we never did.

"We were way below our standards this season, so it's disappointing. We tried to push in the second half and create, but it wasn't to be."

Cahill attracted criticism for momentarily taking his eye off the play to help Jesse Lingard back to his feet seconds before Herrera fired in the shot that doubled United's lead.

But he said his action had been taken to try and minimise the risk of referee Bobby Madley awarding a penalty.

"My instinct was that I was nervous whether it was a penalty or not," he added. "He'd come across and I grabbed hold of him.

"It was an instinct to pick him up. In hindsight it probably looks silly now, but I just had the instinct that the sooner I picked him up on his feet the sooner it stops the referee thinking otherwise.

"But it was irrelevant in the build-up to the goal."

Chelsea's result increases the anticipation surrounding next weekend's FA Cup semifinal meeting with Tottenham at Wembley, and Cahill stressed the need for the Blues to make an immediate recovery.

"We have to react in the right way," he added. "We didn't deserve to win today, so we have to dust ourselves off and prepare for a huge game in the semifinal.

"There are only six games left and we're still in a good position, but we need to realise it's not over. There are points to play for and we need to dig in."