McManaman is still with Real Madrid despite constant speculation linking him with a move back to the Premiership.
"His quality is proven and he knows the Premiership," said Keegan. "He has been with two great clubs, so his pedigree is all there.
"We have talked about him, we have talked about a lot of players but I am sure if you talk to David Moyes at Everton he will tell you Steve is the sort of player you must be interested in if he becomes available."