In other Olympic action, Brazil beat Belarus 3-1 at Old Trafford, thanks to goals from Alexandre Pato, Neymar and Oscar.
Goalkeeper Heurelho Gomes saved from Zlatan Ibrahimovic and Pato, while William Gallas kept Milan at bay with a priceless goal-line clearance from Robinho's deflected shot.
However, an injury to Marco Borriello, Alexandre Pato's stuttering form for Brazil at the Olympics and Filippo Inzaghi turning 35 have made the signing of another striker necessary.
The home side went ahead when Alexandre Pato fed Borriello, who surged inside the area, got past defender Gabriel Heinze and fired from close-range past Marseille goalkeeper Steve Mandanda.
With his contract uncertainty behind him, Beckham seemed to have a new lease of life and he was even given a free role behind forwards Inzaghi and Pato by Ancelotti.
Hamilton's attempt to put together the perfect lap was not helped by several lock-ups, with the McLaren driver coming unstuck at the Bico de Pato and in the Senna S combination.
The keeper's ill-judged dash from goal allowed Pato to round him, and as he struggled to regain his ground Gomes was relieved to see Gallas clear Robinho's deflected shot off the line.
Coach Massimiliano Allegri, knowing the Italians needed a goal, made no concessions to conservatism as Pato, Robinho and Ibrahimovic all started and exerted influence on a first 45 minutes dominated by the Rossoneri.
Milan lost their star forward Kaka to Madrid earlier this summer, and will add Huntelaar to an attacking pool of Brazilians Ronaldinho and Alexandre Pato plus veteran Italian Filippo Inzaghi and Marco Borriello.
As the game entered its final 15 minutes Milan's efforts carried an increasing desperation, but an effort from Pato flew so narrowly off target that the massed ranks of visiting fans thought they had equalised.
The hosts improved after the break but it was still Milan who provided the threat, with Mathieu Flamini and Pato coming desperately close to forcing extra time as the home fans watched the clock counting down with increasing anxiety.
Rafael van der Vaart almost made the visitors pay the price for their ambition with a dipping free-kick that landed on top of the net before Gomes was called into action again to save low down from Pato after he was played in by Ibrahimovic.
The 2008 Beijing Games provided the latest disappointments, with a men's team sporting the likes of two-time world player of the year Ronaldinho and future AC Milan star Alexandre Pato crashing out in the semifinals to Argentina, losing 3-0 and ending up with the bronze medal.
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