Rugby: Sonny Bill Williams hints to prolonged All Blacks career beyond Rugby World Cup

All Black Sonny Bill Williams has suggested that he may continue playing after next year's Rugby World Cup.

It was thought that Williams would likely draw the curtain on his stellar rugby career in Japan, with other commitments such as family and study now taking up more of his time.

But the 51-test veteran told the Sydney Morning Herald that he still "had the fire inside him" to play test rugby and would even consider looking into rugby league offers.

"I've enjoyed the process so far," he said. "And I have to think about what I will do in the future. I am positioning myself in case that becomes an option. I am enjoying doing a bit of studying and keeping my brain going in a different way.

"The last couple of years have been tough with injury, but I still have the fire inside me. I still feel fresh.

"I'm not sure if league is in my future at 33 [but] if there are offers, I will examine it with my family and go from there."

The 33-year-old code-hopping superstar faced off against Australian Bachelorette winner Stu Laundy in a four, two-minute round charity boxing bout on Saturday night, in an event called 'The Banger Under the Hanger'.

There were a few real punches — even a lifting tackle — but it was mostly play-acting as the pair headlined the event to raise money for homeless support charities the Exodus Foundation and Auckland City Mission.

While Williams was 'counted' out by the referee, both fighters were declared the winner, with Laundy announcing his unofficial retirement from boxing straight after.

"I just want to commend Stu and everyone here for making this great night possible, we raised some good money for the serious cause that it was," Williams said after the fight.