Felix Sturm defends WBA title

STUTTGART, Germany -- Felix Sturm has defended his WBA middleweight title by knocking out American challenger Ronald Hearns.

The referee stopped Saturday night's fight in the seventh round when Hearns -- son of Thomas "Hitman" Hearns -- was unable to stay on his feet after taking a couple of heavy blows in the corner.

Sturm, a German of Bosnian parentage, improves to 35-2-1 with 15 KOs, while Hearns drops to 26-2 with 20 KOs.