Watch - Sonny Bill Williams gets KO'd in Sydney

Former All Blacks centre Sonny Bill Williams has lost his unbeaten boxing record after getting knocked out by MMA legend Mark Hunt at the Aware Super Theatre in Sydney.

The 48-year-old Hunt dropped Williams in a telling fourth round with the former NRL star being given a standing count before Hunt sealed the deal with a massive right hand. With SBW barely able to stand, the referee stepped in and waved the fight off.

Williams - who was 9 and 0 coming into the heavyweight bout - was a favourite to beat the combat sports veteran, who had come off a shock loss to another code hopper in the shape of former NRL tough nut Paul Gallen. Gallen went on to be beaten by AFL great Barry Hall, who Williams had dispatched with ease earlier this year.

However, the 130kg Samoan, who had lost over 25kg coming into the fight thanks to a brutal training camp in Thailand, had different ideas. The 'Super Samoan' brought his renowned knock out power to fore, ending the fight at the halfway point with a flurry of unanswered punches.

The 37-year-old Williams, who had been involved in training camps with Joseph Parker and Tyson Fury in the UK this year, returned to ring in 2021 after a successful first stint in the sport nearly a decade ago. The Stan Sports rugby union and rugby league commentator will now have to go back to the drawing board and decide whether or not to continue his boxing career.

There are still fights out there for him. Despite a significant weight difference, the 6'3, 112kg Williams had been linked with a lucrative fight with flamboyant Youtuber turned brawler Jake Paul, who has just come off a remarkable victory over another MMA legend in Brazilian Anderson Silva.

After watching SBW getting dropped, Paul may now fancy giving the New Zealander a spin.