World heavyweight champion Wladimir Klitschko defended his WBA, WBO, IBF and IBO belts on Saturday as he out-classed challenger Francesco Pianeta with a sixth-round knock-out to register his 60th win.
Although German-Italian Pianeta, who survived testicular cancer three years ago, came into the fight undefeated in his 29 previous fights, he was outclassed by the 37-year-old champion in Mannheim, south-west Germany.
Pianeta made an ambitious start with one huge right-hand coming over the top of Klitschko's guard but failing to connect, while the champion responded with two heavy jabs which found their target.
Klitschko relied on his jab in the opening three rounds as the challenger landed several heavy shots, but a big right from the Ukrainian put Pianenta on the floor in the fourth round.
From then on, the challenger was struggling to stay in the fight and although he showed plenty of heart by fighting on, he was down again in the fifth, but managed to survive the referee's count.
With his co-ordination clearly compromised, it was only a matter of time before the fight was brought to an end.
With his trainer ready to throw in the towel, Pianeta did not come up again after hitting the canvas after 2mins 52 seconds of the sixth round after a brutal left-right combination floored him for the last time.
Victory gave Klitschko the 60th win of his career and his 51st knock-out, but the last of his three defeats came nearly a decade ago.