Audley Harrison has convincingly won his fourth fight, knocking out American Julius Long half way through the second round of their heavyweight fight on Saturday fight.

Harrison floored his 7ft 2in opponent with a left to the chin as Long made a lunge at the OIympic super-heavyweight champion.

And a defiant Harrison dismissed suggestions that Long was just another poor sub-standard oppinent lined up for an easy win.

"I knew I was going to catch him. He came here with a good knockout record and I stepped up to the plate," he said.

"He had seven wins and six KOs. You read the national press. Everyone said it was going to be my toughest fight.

"I come from a good pedigree. Being an Olympic gold medallist - it does matter because I've got class."

The fight had a scrappy start, but Harrison soon looked in control against the challenger's clumsy attacks.

After landing a few good punches in the first round, Harrison looked confident in the second and the win did not take long coming.

Harrison had not fought for six months after damaging a muscle in his right arm.

He added: "People say I've got no stamina and I can't punch. Well, what are they going to say about that?

"I've come here after a career-threatening injury and knocked the guy out. I know I've got real substance."