Thomas Tuchel admits he and his players must adopt a "different attitude and mindset" after falling 12 points behind leaders Manchester City at the top of the Premier League.
The Blues followed defeat by City with a frustrating 1-1 draw at Brighton on Tuesday night.
Tuchel gave his players time off this week before facing Tottenham on Sunday.
"We decided we would give the players two days off after Brighton to de-connect a little bit," Tuchel said.
"But the two days alone doesn't solve everything. It was good to have, and after this Tottenham game we will have another chance to give the majority of the players another two days off, because we simply need it.
"But for this Sunday, two days alone are not the solution. We have to make sure we are in a different attitude and a different mindset, and in top shape, because we have a big match."
Chelsea have fallen off the blistering pace set by City, with the Blues having drawn five games and lost twice since the start of the December.
Romelu Lukaku and Hakim Ziyech were spotted having a lengthy animated conversation during the draw at Brighton, but Tuchel believes his players will be refreshed in time for their London derby with Spurs.
"I could see, I could feel from myself and from the team, that some emotions took over, maybe frustration, maybe disappointment," admitted the German, reflecting on his side's draw with the Seagulls.
"It was hard for us on this particular day to reach our top level as a team, whatever top level means on this particular day.
"We did not expect in general that we would play an overwhelming, exciting match, because there's a very strong opponent who has a certain style of play that makes you underperform sometimes.
"But that was the very first time, so when it happens for the first time we should not make a bigger deal of it than it is.
"We've had our two days off now and two days to prepare to be ready for Sunday."
Tuchel is still without Trevoh Chalobah, Reece James and Andreas Christensen as his team prepare to face Spurs for the third time this month, having beaten Antonio Conte's side in the Carabao Cup semi-final.
Fifth-placed Tottenham are eight points adrift of Chelsea in third, but with four games in hand because of because of recent match postponements, Tuchel says he is aware of the need to take three points off their London rivals at Stamford Bridge this weekend.
"It's a big game because of course we can do our mathematics," said the former Paris St-Germain boss.
"But it's strange to see the fixture and see teams competing for the same area of the table and having four games less.
"So this can lead to a wrong impression that you're comfortably ahead when you are not. So we have to make sure that this stays like this."
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