A new addition would place Keane's starting role under threat at Goodison Park but the former Burnley centre-back believes a new signing would only improve his performances.
"I think competition is always healthy and it pushes you on no-matter what position you are on the pitch," Keane told the Liverpool Echo.
"It just keeps you on your toes. We've got competition here but the more the merrier, really.
"It keeps things fresh, makes you work that bit harder and you have to prove yourself every single game and you can't let it slip or you will lose your place in the team."