Manchester United [Images] striker Wayne Rooney [Images] is likely to miss the start of the Premier League season because of a virus he picked up during his club's trip to Nigeria, manager Alex Ferguson said on Tuesday.

"I doubt we'll get Rooney fit for the start of the season with this virus he has had... It's a bad virus, he has not been training," Ferguson told a news conference broadcast on Sky Sports News.

Rooney has not trained since returning from Nigeria, where Premier League champions United played FA Cup winners Portsmouth in a friendly in Abuja on July 27.

The 22-year-old did not play in that match and has missed his club's two subsequent pre-season fixtures against Espanyol and Peterborough.

Michael Carrick has suffered the same virus but United hope the midfielder will be able to play some part on Sunday when they meet Portsmouth again in the Community Shield at Wembley.

Ferguson also reiterated that Portugal winger Cristiano Ronaldo [Images] would not be leaving Old Trafford, despite strong interest from Spanish champions Real Madrid [Images].

The United manager said: "The matter is closed now -- he is a Manchester United player, it is finished. He is going to be a player here next season, believe me."

Earlier on Tuesday, Real president Ramon Calderon hinted at the same conclusion to the long-running saga.

He said the Primera Liga club's new Dutch signing Rafael van der Vaart was "the first and almost certainly the last signing we will make this season".

Ferguson said he would take his time finding a replacement for departed assistant manager Carlos Queiroz, who left his United post last month to take over as Portugal manager.

"I would hope to have someone by the end of September," said Ferguson.

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