Commonwealth Games gold medallist David Nyika has been helping Sonny Bill Williams prepare for his return to the boxing ring and describes the code-swapping star as "class".
Nyika, who won the light-heavyweight division in Glasgow last year to give New Zealand a rare Games boxing success, sparred with the All Blacks midfielder this week.
He posted a video of a three-minute round of the action in the ring with Williams on his Facebook page.
"As promised, a video of Sonny and I getting in some work," he wrote.
"For all the SBW fans AND the haters, here's a sample of the man's class. Keep in mind Sonny had just done 10 rounds, and I hadn't been in the ring for 3 months."
Nyika is based in Hamilton, presenting an ideal source of help for Williams, who is training there with the Chiefs in preparation for his return to Super Rugby.
Heavyweight Williams will end a two-year break from boxing when he fights American veteran Chauncy Welliver in Sydney on January 31.
In the video, his movement looked good and he fired off a couple of combinations that proved tricky for Nyika.
Chiefs and All Blacks loose forward Liam Messam will make his professional boxing debut on the same card.
Williams and Messam are using the same Hamilton gym where Nyika trains.
"Sonny Bill Williams and Liam Messam both got in some good rounds of sparring. The boys are looking super sharp heading towards their fights later this month!" Nyika posted on his Facebook page this week.
Meanwhile, Nyika has taken another step in his campaign to make the Rio de Janeiro Olympics next year.
The gifted 19-year-old plans to step up a division to the heavyweights.
He has taken on a partnership with Hamilton-based supplement store Sportsfuel to help his nutritional programme as he looks to slowly bulk up for the jump in divisions.