AMIR Khan will face his biggest audience when he appears for the first time on American TV on Saturday when his clash with Steffy Bull is screened live on cable channel HBO.

The Olympic silver medallist has proved a prime-time draw on ITV1 with his 11 wins since he turned professional.

And now American fight fans will get to see him, as he joins world champion Joe Calzaghe on an HBO broadcast.

"I want to be as famous in America as I am here," said Khan. "I'd love to fight in the United States and have people know who I am."

Calzaghe puts his WBO super-middleweight title on the line against Peter Manfredo Jr, the runner-up of the American television programme "The Contender".

Khan, 20, is involved in a non-title 10 rounder against Stefy Bull, 24-4-1 (5) a former Central Area lightweight champion and a challenger for the English title.

The fight takes place at the Millennium Stadium, Cardiff, in front of an anticipated 35,000 audience. Meanwhile Bull's manager John Rushton reckons his boxer will be the surprise on Saturday's show and upset the Bolton boxer.

"Khan is not as good as he thinks - and Stefy is better than he believes," says the Yorkshireman.

"Stefy has got to be the best fighter Khan will have faced and is well capable. He has had plenty of time to get fit for it.

"I told Stefy that this was the chance of a lifetime, this is what he wanted to be doing and this is the fight that he claimed he had been looking for.

"It will be no upset if Khan wins but it will be an upset if Stefy wins the fight or gives him a really hard contest.

"Stefy has got to be the best fighter Khan will have faced."

Bull returned to the boxing world less than a week after he announced his retirement and Rushton believes the fight could prove to be a defining moment in his career.

"Up until now, he has always been remembered for fighting Gwyn Wale or for being the Central Area champion, but now he will be always be known for fighting Khan, whatever happens."