Palmer took a hard hit during the match against Manchester United last weekend, following a reckless challenge from Lisandro Martinez. Despite Martinez's dangerous tackle, he was lucky to avoid a red card.
The Chelsea attacker did not train on Wednesday and was seen at Stamford Bridge on Thursday as his side racked up a convincing 8-0 win over FC Noah.
Palmer is not in Chelsea’s Conference League squad so could not have featured regardless but Maresca hinted that the 22-year-old could make a return to the starting XI when they face the Gunners in two days time.
‘Cole is getting better, but because he can walk and have dinner doesn’t mean he is completely fit,’ he said.
‘He is getting better and we still have two days to prepare for the game.
‘Hopefully, we can have him for a session – at least on Saturday – and then we take a decision.’
Palmer has picked up where he left off last season and has already notched up seven goals and five assists in 10 Premier League outings.
He has been virtually ever-present in the Blues’ starting lineup, although he did miss out with illness the last time the two sides met when Mauricio Pochettino’s side suffered a humbling 5-0 defeat at the Emirates.
Weaker opposition in the Conference League has afforded Maresca the option to rotate his squad heavily in midweek, and the Italian insists he will continue to do so to protect his squad.
‘At this moment, we are quite lucky we don’t have injuries, so we have 24 or 25 players available and we can choose,’ he said.
‘The way we have tried to do things since we started the season means we protect players, as it’s one thing to play three matches a week and it’s another to play one.
‘We protect the players in this moment, but it doesn’t mean it’s going to happen all season because there will be a moment where we have injuries or we need to change things.’
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