The former England captain has lifted the lid on how the Scot was angry to see Beckham turn up for the Red Devil’s clash with the Blues at Wembley back in 2000.
The ex-United boss ordered the midfielder to swiftly cut off his hair before the game – and Beckham duly obliged after initially refusing the request.
Speaking in an interview on the Graham Norton Show, which will be aired on the BBC this Friday, Beckham said: “I was in the dressing room with an hour to go before kick off when Sir Alex Ferguson saw it and made me shave it off.
“I said no at first and then I saw his face change very quickly so I went and shaved it off in the toilet. He was very strict.
“It was the reputation of the club, he wanted all the players to look professional and he felt it wasn’t the right look. We were playing at Wembley too, so he kind of had a point!”
Beckham, now 39, scored 62 Premier League goals in 265 games for Ferguson’s United side.
He helped the Red Devils win six Premier League titles, two FA Cups and one Champions League during his decorated spell at Old Trafford.
He also won La Liga and the Spanish Supercup with Real Madrid following his United exit in 2003.
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