Former United hero Beckham took the green and gold campaign to newheights on Wednesday as the AC Milan player draped himself in one ofthe movement's scarves as he left the Old Trafford field after histeam's 4-0 Champions League defeat against his old club.
True colours: David Beckham wears a green and gold scarf and applauds United fans after Milan's defeat at Old Trafford
And the Manchester United Supporters Trust have now written an open letter to the likes of Eric Cantona and Peter Schmeichel aimed at encouraging other Old Trafford icons to visibly support their war against the club's owners.
Part of a letter to MUST's 131,000 members reads: "I'm sure you were watching the incredible moment when Beckham bathed in green and gold. It's moments like this that justify all the collective effort we've been putting into this campaign. We are showing our strength. We are making a real difference.
'We welcomed a legend back to Old Trafford - now we need to capitalise on this moment and bring other United heroes into our fold.
'We've just written a letter to Beckham, Cantona and all of the former United players which calls on them to join our campaign to reclaim United.
'This is our chance to reach out to the United players who built our club - who led from the front and defined United's success over the past decades. But our club is in trouble - we need them to lead United again right here, right now.
Protest movement: United fans with green and gold scarfs and anti Glazer banners during Champions League victory over Milan
'Beckham united with the fans and led by example. Beckham has shown his true colours, now it's up to us to show ours.
'The time to reclaim United is now.'
Membership of MUST has risen steadily since the green and gold campaign began in January but it surged again after Beckham's gesture, with an extra 3,000 fans joining the fold.
With a group of businessmen naming themselves 'The Red Knights' and trying to raise money to buy United from the Glazers, it emerged yesterday that they have appointed Japan's largest investment bank Nomura to help them.
It is also not beyond the realms of possibility that Beckham may be asked to officially join the group, too.
MUST spokesman Sean Bones said last night: 'What Beckham did was a fantastic gesture from the heart of a United legend who cares passionately about Manchester United and its supporters.
'David is exactly the right type of person United supporters would love to see as a future Red Knight.'
Two of the Glazer family were present at Old Trafford on Wednesday to witness a superb performance from Sir Alex Ferguson's team but also a protest against them that reached a crescendo during the last ten minutes.
Last night United chief executive David Gill said: 'There are protests.
'Everyone has the right to protest and there was certainly a lot of green and gold there last night, you cannot deny that.'