Manchester United legend Denis Irwin agrees with critics that the team needs a regular back four to return to winning ways.

Irwin feels a settled back four with captain Nemanja Vidic returning to league action could prove crucial.

"In the last month or so, we've come off the boil a little bit," he admitted on MUTV. "Defensively, we haven't looked as sound this year but we haven't had a settled back-four yet.

"We've attacked at will but, certainly, we need our back-four to be in there playing every week so we need a little bit of luck with injuries."