Danny Mills has warned James McCarthy it will be difficult to make a difference in a struggling Celtic side.
Speaking exclusively to Football Insider, the 19-time England international also claimed the 30-year-old’s Premier League wage demands may complicate any potential deal.
He has recently made a return to the Crystal Palace starting XI meaning Celtic may have to wait until the summer to bring the Republic of Ireland international to Glasgow.
“It’s always difficult,” Mills told Football Insider.
“You’ll be going to a team that is struggling for confidence. Can you turn that around? There aren’t too many players that can walk into a dressing room and lift the dressing room and on their own. It’s hard to create an atmosphere with your performances on the pitch that lifts everybody. It’s very, very difficult to do that.
“You’ve got to be a player on the very top of your game to have a chance of doing that.
“It’s a difficult one. It might be a good move for him, a dream move for him as a fan and financially it might work out.
“But in terms of a football move from the club, does he take them on a level? Does he improve performances? That’s the decision the club will have to take.
“Clearly coming from a Premier League club he’s going to be on decent wages.”
McCarthy has played in the English top-flight for the last 12 seasons after moving to Wigan Athletic from Hamilton Academical in 2009.
He has 13 goals and 16 assists in 263 Premier League games across spells at Wigan, Everton and Palace.