Frank Lampard wants to see "a bit of character" as his side aim to bounce back from a 1-0 home defeat to West Ham, while he refused to blame Tammy Abraham's injury for the result.

Abraham missed the game after suffering a hip injury in Chelsea's 2-2 draw with Valencia on Wednesday, and Olivier Giroud took his place in the starting line-up against West Ham.

Lampard also dropped N'Golo Kante to the bench and watched as West Ham exploited large gaps in the midfield to pick up their first win in eight Premier League matches.

Chelsea will face Aston Villa at Stamford Bridge in midweek before travelling to Goodison Park to play Everton on Saturday, and Lampard indicated he would not make knee-jerk reactions to his side's second home defeat of the league season.

"It can't be one player," Lampard told reporters when asked about the importance of Abraham's injury.

"We arrived back late [from Valencia] and I had to think about how we think about it going forward. We aren't going to get through the season with just 10 or 11 players.

"I think the team out there had enough quality to win this game. There haven't been many times I have said we were below par, hardly at all. Today was one of those days.

"But I don’t think it is time for harsh reactions and judgements across individuals or the team as I see it. It is time for a look at a bit of character to see our reaction against Aston Villa."

Manuel Pellegrini said the result vindicated his decision not to change West Ham's style of play despite their dreadful run of form in the lead up to the game.

The Hammers arrived at Stamford Bridge without a win since September 22, and Pellegrini's future at the club had been the subject of media speculation.

He reflected on a difficult two months, saying: "When you don't win, you are a beast, and when you do, you are a genius.

"I was more worried to convince the players. We know we are not getting the results, but we cannot change the style and must not believe everything we are doing is wrong.

"We were consistent and solid throughout the whole game. But we didn't come here to try to draw. That's the way that this team must play."