LONDON -- Maurizio Sarri has warned his Chelsea players that they must overcome their recent "mental problem" if they want to beat Tottenham.
Chelsea take on their bitter rivals at Wembley on Saturday four points adrift of Premier League leaders Manchester City, but lost ground when they were held to a goalless draw at home by Everton prior to the November international break.
Sarri said after the game that Chelsea were struggling to create the chances to match their possession play, and he believes his team will be punished by a "very dangerous" Tottenham team if they do not improve on Saturday.
"I think it's a mental problem," Sarri said when asked why Chelsea have underwhelmed in recent games.
"In the last three matches, we had problems with the approach to the match. Not only that, because we had some problems also in the beginning of the second half. So we have to be careful. We have to be focused on this problem.
"For sure, it's not a physical problem because, in the last part of the [Everton] match, we ran a lot, I think.
"It's not a tactical problem, because in the first 15 minutes in the last three matches, the problem was the opponents were more aggressive, more determined than us. So it's not a tactical or physical problem. We have to approach the match in a different way, for application and determination.
"[Tottenham] play very good football. They are very dangerous, very dangerous in the offensive phase, very dangerous in the short counter-attacks.
"They are a technical team. In the match, they run a lot, too. From a physical point of view, they are a strong team. They are competitive.
"They will fight for the Champions League positions, for sure, so it's a very difficult match. We must be careful not to lose the ball in our half, because they are very dangerous in these situations."
Chelsea expect to have Eden Hazard back at full strength after he returned to the starting XI against Everton, while Sarri expects Mateo Kovacic to be available despite the ankle problem that sidelined him for Croatia's defeat to England in the UEFA Nations League on Sunday.
Sarri is full of praise for the job Mauricio Pochettino has done at Tottenham, but he reiterated that he does not see either club as genuine title contenders.
"I think that, at the moment, in the Premier League there is a team above the others," Sarri added. "This team is Manchester City. Then there is a very good team, Liverpool. For sure, they will be in the first four positions.
"Then there are four or five teams who will have to fight for the Champions League places: Chelsea, Arsenal, Tottenham, [Manchester] United, maybe somebody else. Usually in a season there is a surprise."
Pressed on whether he sees Chelsea as capable of challenging City this season, Sarri replied: "No, at the moment, no. For me, they are stronger than us at the moment. We have to work, we have to work very hard just to try to recover the gap. But, at the moment, the gap is still there."