Revs skipper Shalrie Joseph was close with his headed attempt in the 12th minute before Pat Phelan's shott was well-held by Anders Lindegaard who was preferred in goal following the retirement of Edwin van der Sar.
United's first real chance didn't come until late in the first half when Fabio skipped down the left and cut it back for Berbatov but the Bulgarian's strong shot was brilliantly saved by Matt Reis in Revs goal before he easily kept out a late Nani attempt.
That gave the Red Devils some impetus and soon enough it was 2-0 when Carrick was played in by Nani's clever downfield ball and the England midfielder set up another substitute, Federico Macheda, and the Italian teenager did the rest with a clinical finish.
Less than two minutes later, the home side hit back thanks to a lucky goal which saw Benny Feilhaber's free-kick from the top of the area deflect off Kenny Mansally much to the chagrin of the United defence.
But the Old Trafford outfit soon restored sanity and their two-goal lead in the 61st minute when Macheda was unmarked at the backpost and finished with ease before United created a gorgeous goal in the 80th minute when Park Ji-sung was played in after some razzle dazzle from Gabriel Obertan on the left before the Korean played a one-two with veteran Ryan Giggs and then chipped in from close range to see off the Revs.