Roman Pavlyuchenko opened the scoring, but two goals in just over a minute from Paul Scholes and Dimitar Berbatov ended the FA Cup road for us in round four at Old Trafford.
Pavlyuchenko's re-directing of a Tom Huddlestone centre and subsequent relatively comfortable containing of the European champions made for a promising beginning, but a double salvo ten minutes before the break turned the contest on its head and the team were unable to secure what in the end would have been a deserved replay.
Just five minutes were showing on the Old Trafford clock when a little spell of pressure resulted in Pavlyuchenko nodding us into a lead. Benoit Assou-Ekotto attempted to cross but was foiled and the ball ran to Tom Huddlestone, who teased in a measured centre that the Russian was able to steal in front of his marker and glance into the bottom corner. Ben Foster was motionless and the home crowd were quieter than before.
The home reaction was predictable and Carlos Tevez was the driving force, carving out space for teammates with selfless and speedy running before rattling the crossbar himself shortly before the 20-minute mark.
Danny Welbeck swapped passes with Dimitar Berbatov and skipped into the area evading challenges on his way but just as it seemed he would level there was one challenge he didn't bank on, Chris Gunter charging in from the right and sliding across at the crucial moment.
United were keen on trying their luck from distance, but Ben Alnwick was not tested until Fabio Da Silva combined with Berbatov and enabled Tevez to let rip from from penatly spot range. Alnwick reacted magnificently and jutted out a hand to divert over.
It was a corner routine that restored parity on 35 minutes, a low corner to the edge of the area from Michael Carrick was met by Paul Scholes, who drove goalwards and the ball flicked up off Huddlestone and found its way into the net.
Less than a minute later Carrick picked out the run of Berbatov who advanced on goal and struck past Alnwick's right hand and United were ahead.
David Bentley took a pot shot from the right in a bid to swing fortune back in our favour, but we were in deficit when the whistle sounded for half-time.
Giovani was introduced after the break in place of Luka Modric, who was a pre-match doubt, and it was a first chance to impress for the little Mexican under the management of Harry Redknapp.
It was Bentley who shifted into a more central role behind Pavlyuchenko, with Gio out on the right. It was a looped cross from Bentley that presented Gareth Bale with the first chance of the half at the far post, but his left foot could not provide the desired direction.
A deflected cross from Assou-Ekotto led to Bentley powering the ball into the side netting in a period when the team were calm and patient in possession and managed to draw the sting from Manchester United.
Breaks were quick with Giovani to the fore, although a counter at the other end resulted in Alnwick having to throw himself low to his right to thwart Ronaldo.
With 22 minutes left Harry opted for the unpredictable offensive weapon that is Adel Taarabt, with Bale withdrawn to make way for the young Frenchman. Jermain Defoe was next on in place of Bentley.
When we really needed to be stepping up the pace, United indulged in some keep-ball and disrupted the momentum generated by the promptings of Huddlestone and the enthusiasm of Giovani.
A combination between Assou-Ekotto and Gio led to the substitute knocking the ball over the bar in front of goal.
Unfortunately it was to be our final opportunity of note.