The Irishman is still hurt at the way he was forced out of Old Trafford when a controversial MUTV interview saw him openly criticise his team-mates individually and signal the beginning of the end of his United career.
Despite not referring specifically to his former team-mate, Keane did state that his advice to players is to look after themselves.
"I think it's always been the case if players fancy leaving and make it hard for a manager and their attitude isn't up to scratch, then you sell them," he declared.
"Having said that, in defence of players, when a club is finished with you, they get rid.
"My advice is look after yourself. If you get a chance for bigger and better things, then go for it.
"I've experienced that myself.
"People question players' loyalty. I question clubs' loyalty.
"It's a business to them. If you're not needed then you can be out of the door in 10 minutes, and I'm speaking from experience.
"It works both ways."