Frank Lampard admits Chelsea's players are in need of a mental boost ahead of Sunday's clash with Manchester City.

After a 17-game unbeaten run that saw them touted in some quarters as Premier League title favourites, Chelsea have lost three of their last five games, winning only one.

A 3-1 defeat to Arsenal was a particular low point, and Chelsea were held to a 1-1 draw by Aston Villa in their last outing on Monday.

Chelsea are tied on 26 points with City, and Lampard said of the match: "It's significant because it's a game we want to win, against a very good opposition.

"They're always going to be there or thereabouts. To be up there with them even without a decent run of form in the last few games is a plus and an opportunity to win a game against a competitor.

"We come off the back of a few games where we've not been at our best and we've dropped some points.

"We had a really long unbeaten run before that so the league table doesn't look terribly bad when you see that we're very close to the top four positions.

"It's important for us mentally because we need to start winning games regularly. City will be hard to do that against."

City have had their own difficult moments this season and have been notably absent from the top-four positions but Pep Guardiola's side have won their last three matches.

A coronavirus outbreak at the club had put the fixture in doubt, with City's match against Everton scheduled for last Monday called off, and they will have five players missing at Stamford Bridge.

Guardiola will be relying on the depth of his squad, and Lampard is expecting a very difficult game.

He said: "I'm confident in us as a team because I know when we play, particularly at Stamford Bridge, we have the opportunity to beat anybody.

"Manchester City are right at the top so, when we beat them 2-1 after restart, it was a difficult game in which we had to suffer at times because they're such a good possession-based team. I know we have to be at our best to win because of the level of opposition.

"In terms of weaknesses, I don't see them. They're a very strong outfit, they're very well managed, they don't concede many and they have lots of threats in attacking areas. If we're at our best then we can make weaknesses against any team.

"We have to keep our energy levels up. We were slow against Arsenal but it need to be quick against Manchester City. We need to be disciplined against them defensively."

Attention also turns to the January transfer window, and Lampard hinted there is likely to be more movement out of the club than into it.

He said: "We have a big squad and we'll see if that changes. Are there opportunities for players who aren't playing so much? That will be a conversation between player, club and myself.

"And then we'll see if we can strengthen in the right way, but we're not jumping up and down to do so. My focus this year is purely on work because we have young players."