Sonny Bill Williams looks to revive boxing career as he confirms rugby retirement

The last of Williams’s seven professional fights was a convincing points decision win against American journeyman Chauncy Welliver in 2015

Sonny Bill Williams during a New Zealand All Blacks squad training session at Tatsuminomori Seaside Park in Tokyo. Picture: Brendan Moran/Sportsfile

Sonny Bill Williams says he will focus on becoming a champion boxer after conceding his body can no longer stand up to the rigours of rugby league.

Williams, who won two rugby union World Cups for New Zealand in 2011 and 2015, has dabbled in boxing since a first professional bout in 2009 but the 35-year-old plans to get more serious about it after building a gym in southern Sydney.