The 25-year-old Klitschko was making his third defence of the title in front of 10,300 spectators.

His record now reads 37 victories, 35 inside the distance, and one defeat.

Botha, the former IBF belt holder, gave Klitscho some trouble in the early rounds with holding tactics, but began absorbing heavy punishment in the fifth.

The knockout came when Klitschko hit Botha with a straight left, several more rights and a short left uppercut.

"I wanted to pressure him, but it didn't work. He hit very hard. He moved very well for a big man - I wasn't expecting that," said Botha.

Klitscho's camp said their fighter will have his next camp in the United States as he tries to prove that he's the up-and-coming fighter in the division.

"I just want a fight soon, I don't want a long layoff," said the 25-year-old Klitscho.

"Against Botha, I just had in mind how Lewis and Tyson did against him," he added.

Lennox Lewis destroyed Botha in two rounds, while Mike Tyson finished him off in the fifth.

Botha's trainer Abel Sanchez was impressed with Klitschko, but feels he is not ready to challenge either man just yet.

He said: "I think Lewis is a little bit more experienced and mature, but give Wladimir four or five fights against the top people and he'll get there."