Chelsea boss Antonio Conte said he took responsibility for failing to motivate his side in Sunday’s defeat by Manchester United.
The Blues lost 2-0 at Old Trafford and are now just four points ahead of Tottenham at the top of the table, having led by 10 points in March.
“We didn’t play a good game and United deserved to win the game,” said Conte.
“They showed more desire, more ambition, more motivation. In this case the fault is of the coach.”
The Italian added he had not been able to “transfer the right concentration, desire, ambition to win this game”.
Spurs have put themselves into title contention with a run of seven successive league wins, while Chelsea have had two losses in their past four games.
The teams meet at Wembley on Saturday (17:15 BST) in the first of the weekend’s FA Cup semi-finals.
“I have concern because we have to work together and find quickly the right ambition to win this title,” said Conte.
“If someone thinks it’s normal for Chelsea to win the title, we started as underdogs after 10th place last season.
“Tottenham is in good form and playing with enthusiasm. We must find the same.”