Wladimir Klitschko knocked out Tony Thompson in the sixth round on Saturday at the Stade de Suisse in Berne, Switzerland, retaining his WBA, IBF and WBO heavyweight title belts.

Klitschko, who improved to 58-3 with 51 knockouts, also stopped Thompson (36-3) in the 11th round in 2008.

On Saturday, the Ukrainian used a big right hand to drop Thompson in the fifth round. And another knockdown in the sixth was too much for the 40-year-old American to recover from.