Pep Guardiola said Benjamin Mendy needs minutes in order to return to peak form after selecting the Frenchman in Manchester City's starting line-up against Chelsea.
Mendy's City career has been plagued by injuries and his start against Chelsea is just his fourth in the Premier League all season.
"He needs time," Guardiola said of Mendy, who has played just 31 times for City since joining the club from Monaco two-and-a-half years ago.
"We know his quality. He needs games and minutes and games and games and after he will come back in his best form."
On his decision to select Mendy and Joao Cancelo as City's starting full-backs against Chelsea, with Kyle Walker and Angelino dropping to the bench, Guardiola said: "These two guys play today, nothing special."
Guardiola praised Chelsea ahead of the game, with the Stamford Bridge club starting the match one point and one place above City in the Premier League table.
"Their spirit, they are free in their heads and they play good," Guardiola said of Chelsea's strengths. "Individually, the quality of the players they have... it's a top, top-class team."
Guardiola said there is little difference between Chelsea under Maurizio Sarri and Chelsea under Lampard, despite the team's perceived improvement under their former midfielder.
He said: "Some defensive moments are a bit different but the way they play is quite similar and the same intensity, the same aggression up front and the quality in all the players they have."
