The England international was caught by a heavy challenge from Lisandro Martinez in the 1-1 draw at Manchester United on Sunday but was rested midweek as the Blues ripped apart Armenian Premier League FC Noah.
Maresca spoke in his latest press conference about the 22 year old who has been seen walking unaided in the past few days as he makes a slow return to training.
“He’s getting better,” Maresca said. “(Just because) he can walk and have dinner it doesn’t mean he is completely fit but we still have two days to prepare the game.
“Hopefully we can have him for the session at least Saturday and then we’ll take a decision.”
Palmer was selected in England’s squad for the upcoming Nations League fixtures against Greece and the Republic of Ireland which suggests his injury is not as serious as once thought.
This weekend’s fight against a struggling Mikel Arteta side could be crucial in Maresca’s fight for a top four finish this season and having Palmer fit could be the difference maker at Stamford Bridge.