Wladimir Klitschko has retained his WBA, WBO, IBF and IBO heavyweight titles with a sixth-round stoppage against Tony Thompson in Switzerland.
It was the second time that the pair met inside the ring; their 2008 bout in Hamburg ended with the Ukrainian knocking Thompson out in the 11th round.
Klitschko dominated the contest at the Stade de Suisse in Berne, and the referee was forced to wave the fight off after the champion had sent the 40-year-old mandatory challenger crashing to the canvas in the sixth.
The victory means that Klitschko has improved his record to 58-3 and brings his knockout count up to 51.
