United's future burns too brightly for ageing Milan

There are very few people capable of upstaging Manchester United when they have just scored four goals at home against one of the most famous clubs in Europe, but it just so happens that David Beckham is one of them.

As he stopped before he left the pitch to put on a green-and-gold scarf, the key weapon of protest against the hated Glazer ownership of United, so Beckham produced the Kodak moment of the evening. Wayne Rooney may have scored twice to reach 30 goals for the season but this was bigger: in those few brief seconds Beckham ensured himself a place in the folklore of Old Trafford.

You could argue that it was the most radical thing Beckham has ever done. He is by instinct a fence-sitter, a man whose corporate sponsors have demanded over the years a certain level of blandness. Speaking after the game he tried to distance himself from the anti-Glazer cause, claiming he was simply a fan of the club, but the deed was already done.

The moment the most recognisable sportsman in the world attached himself to a grass-roots movement trying to take control of a billion-pound football club was not insignificant. It will live on in thousands of protest banners. As an antidote to the corporate takeover of football, from the grandstanding of the so-called Red Knights to the mountainous debts of the Glazers, it was the moment when fan activism carried the day.

Needless to say, United's loyal in-house channel MUTV stopped playing the footage of Beckham leaving the pitch before he picked the scarf up from the pitch. That told you all you needed to know about the likely official reaction. For Beckham it seemed to be an instinctive response to one of the most affectionate, appreciative welcomes Old Trafford has granted to a former player.

On his return to Manchester, Beckham was ignored by his old manager. Sir Alex Ferguson had resolutely refused to be drawn into the Beckham love-in, devoting not a single word to him in his match-day programme notes. Instead it was the Old Trafford crowd – never the easiest bunch to win over – who gave Beckham the welcome back he must have dreamt of.

It was pretty much the only consolation for Beckham on a night when his old friends in red reduced this venerable Milan team to an irrelevance. In fact, it was embarrassing for the Italian side, who ended the game as a rubble of famous names who were barely recognisable as their old selves and could not get off the pitch quick enough.

As they marched into the Champions League quarter-finals you could never imagine a United team being permitted to grow old and stale in the way Milan have. While Beckham, who came on with only 26 minutes to play, may have looked on with envy at the starting place for his old amigos Gary Neville and Paul Scholes, this really this was another evening in which the future of United burnt brightly.

Last night, Rooney was exceptional and Park Ji-sung and Darren Fletcher chipped in with the other goals. On the wings, Antonio Valencia and Luis Nani were wonderful. Even Neville, playing at right-back in his 16th start this season at the ripe old age of 35, suggested that he could still cut at this level. In fact, he was more of an attacking threat than Ronaldinho, the man he was marking

Surging forward in the first half, Neville hit three crosses. Two of them went straight into the East Stand. The other one was placed perfectly on Rooney's head to score United's first. You could pay Neville no greater compliment than by saying it was a Beckhamesque delivery.

Rooney's opening goal after 13 minutes took the sting out the tie. It left Milan requiring three goals to win it and no discernible means by which to score them. Brilliant in the first half of the first leg, Ronaldinho was terrible last night. Apart from one header that went wide in the first half, he barely had an influence on the game.

As Arsenal had done to Porto on Tuesday night, United set about Milan right from the start. In defence, Rio Ferdinand and Nemanja Vidic were excellent, a throwback to their dominant performances two years ago. There was a half-chance for the hapless Klaas Jan Huntelaar that went begging. Park marked Andrea Pirlo out the game.

Rooney got in front of Daniele Bonera for the first goal and, with one flick of the head, put Neville's cross beyond the reach of the Milan goalkeeper Christian Abbiati. He finished the game off in the first minute of the second half when Nani on the left wing played a ball with the outside of his right foot and Rooney clipped it past poor old Abbiati.

From then on it was played at the pace of a testimonial, the United fans giving Beckham a tremendous reception when he came on. Before then Park had scored the third, played in by Scholes. Park even slipped before he scored – so slow were the Milan defence that they never got a tackle in.

Beckham had one decent volley that was punched over by Edwin van der Sar. Fletcher scored the fourth with a back-post header from Rafael da Silva's cross. By the end of the game the mood had changed in Old Trafford. "Love United Hate Glazer" banners were unfurled on the Stretford End and green-and-gold scarves were held up above heads all over the stadium.

The one that Beckham put around his neck had been thrown on to the pitch in front of him as he made an emotional departure. He wore it for just a few paces before he disappeared down the tunnel but, as acts of insubordination go, it was more than enough.

Manchester United (4-3-3): Van der Sar; Neville (Rafael Da Silva, 66), Ferdinand, Vidic, Evra; Fletcher, Scholes (Gibson, 73), Park; Valencia, Rooney (Berbatov, 66), Nani. Substitutes not used: Kuszczak (gk), J Evans, Obertan, Diouf.

Milan (4-3-3): Abbiati; Abate (Beckham, 64), Bonera (Seedorf, h-t), Thiago Silva, Jankulovski; Flamini, Pirlo, Ambrosini; Huntelaar, Borriello (Inzaghi, 68), Ronaldinho. Substitutes not used: Dida (gk), Gattuso, Zambrotta, Favalli.

Referee: M Busacca (Switzerland).