Palmer’s injury concerns come in a World Cup season, with fierce competition for a place in England’s squad, let alone for the number 10 role.
During the last international camp, Three Lions boss Thomas Tuchel said he will only call up two players for that position.
Jude Bellingham and Morgan Rogers started in the World Cup qualifying wins over Serbia and Albania, while Phil Foden came off the bench in both games and Eberechi Eze played out wide.
Chelsea captain Reece James, usually a right-back and previously used there by Tuchel for England, also played 90 minutes in midfield at Bournemouth and Atalanta this week.
Asked if James will start a third straight match, Maresca said: “Could be, yes.”
On whether it was out of necessity, he added: “We need Reece – not only in this game, but in all games.”
The switch is due to Moises Caicedo serving a three-match ban, which ends after Saturday’s game, and Lavia being injured.
Maresca continued to defend Chelsea’s rotation policy, which has come under scrutiny during a four-game winless run after making more than 100 starting XI changes this season.
“If you look at our first XI in games like Arsenal, Barcelona, Atalanta, Tottenham and Wolves at home, it’s the same eight or nine players – [Marc] Cucurella, Enzo Fernandez, Wes Fofana, Trev Chalobah, Pedro Neto, Joao Pedro, Malo Gusto, Reece James. They always play.
“If you go from Bournemouth to Atalanta, you mention five changes, but the same eight or nine players are always there.
“This season is a marathon, not a sprint. If you always use the same players, you will struggle with fitness and keeping them healthy.”