Manchester United hero Denis Irwin believes no-one will see Sir Alex Ferguson's retirement coming.

Irwin believes Fergie will tell no one when he's quitting.

Former United fullback Irwin said: "When he finishes it'll be quick, clean and that will be that. He won't warn anyone and we won't see it coming. It'll be a clean break, he won't move upstairs or anything like that.

"He certainly likes challenges and with City improving he may want to face them down for another year or two.

"He'll have other ambitions too. Passing Liverpool on the roll of honour is one and he might do it this year. I'm sure he feels he should have won more than two Champions League titles, too, but whenever he goes it'll be quick and sudden."