The France international completed a £40m move to Ligue 1 side AS Monaco in the 2017 summer transfer window.
Bakayoko was signed to bolster Antonio Conte’s midfield before the surprise sale of Nemanja Matic to Manchester United.
The 23-year-old played a key role in Monaco’s title success last term after the Ligue 1 side finished above Paris Saint-Germain.
However, Bakayoko has struggled to adapt to the Premier League to prompt criticism of the powerful midfielder.
The French star produced a particularly disastrous performance in Chelsea FC’s 4-1 loss to Watford earlier this year.
Former Chelsea FC defender Gallas believes Bakayoko shouldn’t be judged until the end of the 2018-19 campaign.
“He has to adapt as well to Premier League football, you have to give him time. That’s why it is really difficult to speak before, I like to give time to the players and the manager,” Gallas told Goal.
“For me, if I have to judge him, I will do it next season. For me, this season is about adaptation. Everything changed for him.
“Football, language, maybe the family, maybe it is difficult for him to find an apartment or a house and to feel good. I will judge him next season.”
Chelsea FC won the Premier League title with two games to spare last term after finishing seven points ahead of Tottenham.
The Blues can still finish this season with some silverware if the title holders manage to beat Southampton to reach the FA Cup final.
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