DURBAN, SOUTH AFRICA - AUGUST 29, Francois Botha 'White Buffalo' during a boxing and sparring session at Train Gymnasium on August 29, 2012 in Durban, South Africa Photo by Steve Haag / Gallo Images

Johannesburg – Former world heavyweight boxing champion Francois Botha says New Zealand Rugby World Cup gold medallist Sonny Bill WIlliams should rather have fought his son ahead of their clash in Brisbane, Australia on Friday.

“When I catch him he's going to go,” Botha said about their tussle.

“I'll drag him into deep water and let him drown. He's never fought a guy like me, it's stupid. Sonny should have fought my son, my son would kick his butt and he's not even a professional.”

Quade Cooper, the enfant terrible of Australian rugby, would also make his pro boxing debut on the undercard.

Botha has had 60 fights and Williams just five, but the New Zealander is younger, stronger and fitter.

However, anyone who dismissed the 44-year-old “White Buffalo” from South Africa could be making a big mistake.

He brings tons of experience, having fought the who's who of the division, and still knows how to look after himself in the ring.

Williams, who has vowed to retire if he lost, is unbeaten, but had not fought anyone vaguely world class.

“I can see myself doing boxing full-time in the future, but for that to come to fruition I need to fight guys like this and beat them, otherwise it's a waste of time,” Williams said.

“Some boxers go their whole lives building a record until people want to watch them. I've had to jump really quickly. This fight will be defining. It will tell me if I can keep going.”

The key for Williams would be to box behind his jab, using speed and movement to keep Botha at bay.

Botha loves nothing more than a tear-up and would want to engage at close quarters, catching Williams on the break.

“Sonny Bill looks like a Hollywood movie star. The trouble is he fights like one too,” Nathan said. – Sapa