SPRINT king Usain Bolt yesterday begged Sir Alex Ferguson for the chance to play for Manchester United — but warned he would have to be quick.

Bolt: I want a trial for Manchester United

The Olympic 100m champion told of his dream after being asked about his next challenge.

Bolt, 25, said: “People think I am joking. But if Alex Ferguson called me up and said, ‘OK let’s do this, come and have a trial’, it would be impossible for me to say No.

“I would not take up the challenge if I didn’t think I was good enough. I am a very accomplished player and know I could make a difference.

“I would be the fastest player in the team — but I can play as well.”

The 6ft 5in Jamaican added: “I am in Britain for a few more days. If Alex Ferguson wants to give me a call he knows where I am.”

Bolt — who thrilled the world with his 9.63 seconds victory on Sunday night — has been pals with Sir Alex and his stars since visiting Manchester in 2009 to take part in a 150m sprint through the city streets.

He said recently: “I definitely want to see what I could do. I think I could step up to the Rooneys.”

Last night fans backed his call. Adam Haworth, 35, of Bury, Gtr Manchester, said: “We could have done with a bit more pace and power last season!”

Chris Hicks, 49, from Manchester, said: “We should stick him in the reserves for a year to train him up — then when Ryan Giggs retires we’ll have a ready-made replacement.”

A United spokesman said: “As the fastest man on Earth he would undoubtedly add speed to the team.”

Bolt won the most hotly-contested sprint ever before an 80,000-strong crowd at the Olympic Stadium in Stratford, East London.

The fans included his cousin Vinette Jones, 53, who travelled from her home in Bristol with children Matthew and Lemara. Vinette said: “We’re so proud of him.

“Some people seemed to doubt him because he lost a couple of big races beforehand. But we were confident.”

Matthew, 25, said: “I often play against Usain on Call Of Duty on the Xbox.

“My brother Ryan gets his old trainers because they both have size 13 feet.”

Bolt’s aunt Betsy Davis flew in from Jamaica but could not get a ticket — so watched on TV at sister Maureen’s home in Wolverhampton.

Betsy, 43, said: “It was lovely watching it together with family.

“It was electrifying. I have been speaking to family members back in Jamaica and they are all so excited.”

Bolt wound down by posing for a snap with girls from the Swedish handball team. He posted it on Twitter at 3am with the words: “A gaza we say hummm mmm.”

Last night he was presented with his medal at the stadium.

He was cheered along with second-placed team-mate Yohan Blake, 22. But bronze-winning US sprinter Justin Gatlin — banned for four years in 2000 for drug-taking — was BOOED.

– USAIN Bolt broke a TV record too — with a staggering 20 million Brits tuning in for his 100 metres sprint win.

Overnight ratings showed 19.4 million watched on BBC1 with 600,000 more “red button” viewers — making it the UK’s biggest ever Olympics audience.