Palace have been terrible so far this season and are yet to claim a point or even score a goal.
Roy Hodgson's side have suffered heavy defeats to both of the Manchester giants in their last two outings and host the Premier League champions on Saturday.
Chelsea will be without two of their stars with N'Golo Kante and Alvaro Morata out injured.
And Merson says the duo’s absence will mean the Blues won’t be able blow Palace away like their title rivals did.
He told Sky Sports: “This is a hard game for Chelsea without N'Golo Kante or Alvaro Morata.
“They are two massive players and not having them will make a difference.
“But Chelsea still have a good defence and Palace don't have Christian Benteke so it will be hard for them to score.
“Man City were on fire against Chelsea and still only scored once, and that was a 'worldie', so that is what Palace are up against.”
Chelsea are currently a point and place behind their London rivals Tottenham in the Premier League table.
Spurs take on Bournemouth this weekend looking to finally claim their first league win of the season at Wembley.
Merson added: “I go with Tottenham every week at Wembley and they haven't won yet, but it has to come soon, surely?
“This is a nice game. Bournemouth are struggling this season and they are not going to boot you off the pitch.
“You have to remember that teams going to Wembley pick their game up. You ask any footballer if they could score a hat-trick anywhere they would pick Wembley.
“Everybody raises their game at Wembley and Spurs need to sort it out. Against Burnley they were 1-0 up and with 20 minutes to go you saw they were getting nervous and in the end Burnley scored.”
