Wladimir Klitschko completed his 17th consecutive title defence as he knocked out Kubrat Pulev inside five rounds in Hamburg on Saturday night.

The International Boxing Federation, World Boxing Association and World Boxing Organization heavyweight champion would floor his opponent three times before a left hook secured victory.

It is the first defeat that Bulgarian Pulev has suffered in 21 fights and extended Klitschko's record to 63-3 with the 53rd knockout of his career.

Pulev tested Klitschko with a stiff jab in the opening stages and the crowd were clearly behind him but the Ukrainian responded, flooring his opponent with a left hook.

The Bulgarian got back to his feet but moments later he was down again, although it appeared to be a shove from Klitschko. Pulev saw out the first round on his feet.

Klitschko had the better of the second as Pulev kept his distance but the challenger appeared to have recovered before he was put down again in the third. That left the Bulgarian with a cut above his left eye and Klitschko continued to punish his opponent with a series of well-aimed punches. The last of them landed in the fifth round and sent Pulev down and out of the fight.