Antonio Conte conceded Tottenham have the momentum to be champions after falling to old foe Jose Mourinho at Old Trafford.
A 2-0 defeat by Manchester United – their second loss in four matches – left the Blues only four points ahead of Tottenham with six games remaining.
Conte says he is worried that Spurs, who have now won six on the bounce, now have the momentum in the run-in and could inflict further psychological damage on his side by beating them in their FA Cup semi-final at Wembley on Saturday.
He said: “It won’t be easy because Tottenham are now the best team. They are in good form and playing with enthusiasm – we must find the same.
“They are feeling the possibility to write history and it is important to know this.
“I have concern because we have to work together and quickly find the right ambition to win this title. If someone thinks it’s normal for Chelsea to win the title, they must remember we started as underdogs after 10th place last season.”
United manager Jose Mourinho was relieved to gain a win that keeps their top-four hopes alive.
“The satisfaction is for different reasons,” he said.
“After Liverpool and Manchester City’s victories, if we didn’t win then goodbye top four. And when you beat the leaders it is obviously a very good feeling.”
Rashford, the scorer of United’s first goal, said: “It was a clever pass from Ander Herrera, we made eye contact and he put the ball exactly where I want it. It’s something we need in this team.”
Mourinho has masterminded plenty of wins in big games down the years, but he usually does it with a defensive approach and by setting up with a team that, first and foremost, is very difficult to break down.
On Sunday, he flipped that model on its head. United played with two up front and with wing-backs who were high up the pitch – they were on the front foot and went at Chelsea from the start.
It meant United produced a brilliant attacking display as well as a convincing defensive one that was tactically aware of the different threats that Chelsea posed.
Mourinho asked Ander Herrera to man-mark Eden Hazard and he did it brilliantly, but United’s game-plan went much further than that.
They did not give Chelsea an inch of space anywhere on the pitch and did not allow them to get into any type of rhythm.
It started from the front, where Marcus Rashford and Jesse Lingard never stopped pestering the Blues defence, and Paul Pogba, Marouane Fellaini, and Herrera seemed to win every meaningful battle in midfield.
When the ball did reach Blues striker Diego Costa, he always seemed to end up on the floor because Eric Bailly and Marcos Rojo put him under so much pressure.