The France international moved to the defending Premier League champions in a £40m deal in the summer transfer window.
Bakayoko’s arrival triggered Nemanja Matic’s controversial £40m switch to their bitter title rivals Manchester United.
The Serbia international helped Chelsea to win the Premier League title in 2015 and 2017 before his switch to Old Trafford.
Bakayoko started the season with a knee problem before he forged a partnership with PFA Premier League player of the year N’Golo Kante.
The 22-year-old defensive midfielder has struggled over the past month or so as the summer signing continues to get up to speed in the Premier League.
Former Chelsea midfielder Lampard believes Bakayoko needs to raise his performance level following an unconvincing start to his Blues career.
“Bakayoko, it’s been well documented, hasn’t settled quickly at Chelsea and English football,” Lampard told BT Sport.
“He has to come to grips with that. He needs to improve. Antonio Conte has got options, Danny Drinkwater can play as well, but hopefully Bakayoko will improve.”
Chelsea are in third place in the Premier League table and 11 points behind current leaders Manchester City.
The Blues signed six players in the summer transfer window as Antonio Conte looked to improve his squad depth ahead of a return to the Champions League.
The title holders secured their spot in the Champions League last-16 draw despite a 1-1 draw with Atletico Madrid last term.
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