Wayne Rooney has said that Manchester United could require more fresh faces if they are to mount a Premier League title challenge.

The Red Devils' acquisition of Fred from Shakhtar Donetsk for around £52m is their most expensive signing this summer, while defender Diogo Dalot and goalkeeper Lee Grant have also arrived at Old Trafford.

United are reportedly attempting to sign a new centre-back before the window closes, and Rooney has admitted that it may take such an addition for his former club to compete for the title.

"I think it will be difficult after the season they had last year. [Manchester City] have been playing some great football," the DC United striker told Sky Sports News.

"But I hope someone can catch them - it would be nice, so hopefully Manchester United can. I think maybe another signing or two. I am sure Jose [Mourinho] has been getting the team right. I know there has been a lot of talk about pre-season in the press but I am sure behind the scenes, Jose has been giving them the right amount of work.

"They have the game against Leicester on Friday so hopefully they can go one step further this year than second and try and get the title back."

United ended their pre-season programme with a 1-0 defeat to Bayern Munich.