Sir Alex Ferguson deployed the 25-year-old England forward on the left for UnitedÃ¢â‚¬â„¢s goalless draw with Marseille in the first leg of their last-16 Champions League tie on Wednesday.
But the England international, who has netted six goals in 22 appearances this season, struggled to make an impact and was moved back to his favoured central position following the introduction of substitute Paul Scholes.
“When you are played wide left it is difficult to adjust if you haven’t played there for a while,” Rooney told Uefa.com. “But we’ve got a lot of injuries at the minute, so I don’t have a problem [playing on the wing].
“It was quite a difficult game for us. Marseille didn’t cause us many problems but we didn’t create as many chances as we’d have liked either.
United boss Ferguson was without a number of first-team regulars in France including captain Rio Ferdinand, Ryan Giggs, Ji-sung Park and long-term absentee Antonio Valencia.
“We had a few big players missing and I think they would have made a difference had they been here,” said Rooney. “We’ve got Marseille at home now and we know that if we beat them we’re through to the next round.Ã¢â‚¬Â
The former Everton striker added: “We’re confident at home and we have to be positive.”
Meanwhile, United are expect to be fined by Uefa after some travelling supporters lit flares at the Stade VÃƒÂ©lodrome during Wednesday’s clash. Seven United fans were arrested by French police, four for possession of flares.
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