Berbatov netted his 22nd goal of the season when he was given the benefit of the doubt with a very tight offside decision.
Valencia doubled the lead just after the half-hour when he nodded home from close range after Aaron Hughes had tried to clear Nani's goalbound effort.
1-0: Dimitar Berbatov opens the scoring for Manchester United
2-0: Antonio Valencia heads the ball in from close range
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