I'm not a cheat, insists Peterson

Lamont Peterson, who failed a drugs test after his controversial bout against Britain's Amir Khan last December, says he took the synthetic testosterone for medical reasons and insists he is not a cheat.

Peterson says he did not take testosterone to enhance his performance and has rejected calls from Khan to surrender his WBA and IBF belts.

The pair were due to have a rematch on Saturday in Las Vegas after Khan lost his light-welterweight world titles to his American counterpart in Washington DC last year, but it was called off after Peterson tested positive.