The England midfielder made an emotional return to the club where he made his name, only to see a rampant United crush his AC Milan side.
Beckham, however, still made sure that he grabbed the headlines as he plucked a green and gold scarf from the pitch at full-time and draped it proudly round his neck.The campaign has grown every week since it was launched in January as a symbol of defiance against the Glazer family who own United.
Evergreen and gold: Beckham walks offsporting the anti-Glazer colours
But Beckham's gesture, watched from the directors' box by Avi Glazer, represents one of the most significant moments yet.
He said: 'I am a Manchester United fan and I support the club. Ialways will. I saw the scarf there and just put it round my neck. It'sthe old colours. That's all I know. It's nothing to do with me how it'srun. That's to do with other people. I support the team.'
Glazer had already endured a difficult night as Sir Alex Ferguson'steam put on a majestic performance against a backdrop of anti-Glazerprotests.
Knockout: Wayne Rooney wheels away after scoring his second goal
On the field, United's performance was notable for two more goalsfrom the remarkable Wayne Rooney. The striker has 30 this season and itis possible he could even beat the 42-goal haul of former United wingerCristiano Ronaldo from two seasons ago.
United manager Ferguson said: 'There's a challenge for him now andhe will be aiming for it. I was happy for him to get to 30 goals but hekeeps improving. Tonight he was sensational. I thought our second-halfperformance was marvellous. When we play with that tempo we aredifficult to play against.'
Centre of attention: David Beckham congratulates Manchester United striker Wayne Rooney
On a dramatic night in Europe Ronaldo and Real Madrid went out 2-1to Lyon on aggregate. This removes one significant obstacle for Unitedas they seek to reach the final for the third season running.
Ferguson added: 'With this team of ours it does not matter who we play. We have that confidence now.'
Beck at Old Trafford: David Beckham sends over a trademark cross
The night was glorious for United but not so for Beckham. The formerEngland captain was left on the bench at the start and did not appearon the field until the 62nd minute seemingly with a tear in his eye.
Beckham did threaten to score with one volley and almost set up agoal with a late cross. He received a rapturous ovation from the OldTrafford supporters and swapped shirts with Rio Ferdinand afterwards.
Beckham said: 'It was very nice to be back and yes it was emotional. I don't know if I had a tear in my eye or not.
'It's a disappointing night in terms of the result. They are a verygood team. When you don't start the game it's always frustrating.
Support act: Manchester United fans hold a banner for David Beckham
'I wanted to play but I'm part of a team and we have to win togetherand lose together. I keep saying that Wayne Rooney is such anexceptional talent and that is obvious. Without doubt he's one of thebest players in the world at the moment.
'This is possibly the last time I will play at Old Trafford and Ihave been given some great memories from the fans. The way they gave methat reception was terrific and I'll never forget it.'
Welcome return: David Beckham (centre) with Milan coach Leonardo (second right) as he prepares to come on as a second-half substitute
Ferguson added: 'We expected that reception for David. I think hedeserved that. He was a great player, he had a great spell here.Normally they always applaud our players, the ones who have had greatcareers here.'
Milan coach Leonardo conceded that United had 'dominated' and addedhis own tribute to Rooney, saying: 'Rooney can grow up even morebecause he is still young. He's a complete player, strong, fast and heworks hard.
'He does a lot of incredible movement and he's playing in a systemthat is perfect for him. United play at such speed and often on thecounter-attack. That system, with Rooney, is incredible.'
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