Enzo Maresca has admitted morale inside the Chelsea camp is low and that his players are 'upset'.

The Blues have won only twice in their last nine Premier League games and their hopes of qualifying for next season's Champions League hang in the balance.

They have slipped from second in the table to sixth behind the likes of Manchester City and Bournemouth, which has increased the pressure on Maresca after an impressive start to the season.

Ahead of a crunch clash with Aston Villa on Saturday, the Italian refused to hide the fact his players are not happy with the current situation.

"The team spirit in this moment has to be upset, in terms of they have to be upset," Maresca said.

"We have to be upset because we are not happy with the results.

"We are all aware we are in a club where we are not here to survive, but to fight to win titles. They are the same players that for 19-20 games were [in the] top four, second for the most part of the season.

"For sure, after this moment, they are going to be better players and better professionals."

Chelsea have been dealt with injuries to key players, losing Wesley Fofana and Benoit Badiashile at the same time before the New Year. Romeo Lavia also hasn't stepped out onto the pitch since December and continues to be sidelined.

More recently, Maresca has been forced to deal with a double blow after Noni Madueke and Nicolas Jackson were ruled out for several weeks. And the 45-year-old suggested the loss of those squad members has been a factor in their decline.

"It's an important part. Reviewing the first game against them [Aston Villa], with more physical players like Wes and Romeo, even Nico, this is the reason why probably in this moment we struggle a little bit in terms of results.

"After the international break, we probably have all of them but before that, we will try and win the games."

After hinting 18-year-old winger Tyrique George could be handed more minutes in the coming weeks, Maresca also addressed Robert Sanchez's situation following his admission that Filip Jorgensen is his No.1 choice last week.

The Spaniard showcased his brand new look in training on Thursday after opting to shave his head entirely bald, as the stopper looks to win back his place.

And Maresca could not resist the opportunity to make a joke at his expense to lighten the mood.

When asked about Sanchez's new hairstyle, Maresca joked: "I said to him 'if you want to play again, you need the same haircut as mine' [laughs]."