World heavyweight champion Lennox Lewis has been told he will face a new and improved Francois Botha at London Arena on Saturday.

The South African challenger lost in five rounds to Mike Tyson but says he has worked hard to make sure the same thing does not happen against Lewis.

"After the Tyson fight, I started lifting weights and my punching power has increased enormously," said Botha.

"When he (Lewis) wakes up he's going to ask 'what happened?'. They are going to say 'well, you got knocked out'."

Botha is not expected to beat Lewis but he showed against Tyson that he cannot be taken lightly.

The White Buffalo, who has also been nicknamed 'The Tiger' and 'The Bomb', once fought three times in a night.

Art Hooks, Russell Rierson and Mike Jones were all knocked out inside a round on an officially sanctioned bout in Oklahoma City in 1992.