All eyes on Williams at Chiefs this week

He is the New Zealand Professional Boxing Association heavyweight champion but it remains to be seen whether Sonny Bill Williams will be fit to play for the Chiefs next weekend.

Williams pulled a hamstring when undertaking sprint training in the build-up to last week's fight against Clarence Tillman III and the management at his new Chiefs franchise will be keeping a close watch on how he trains ahead of their final pre-season hit-out against the Hurricanes in Taupo on Friday.

Coach Dave Rennie said Williams' hamstring tear, suffered in Sydney when training with former Sydney Roosters sprint coach Roger Fabri and alongside Parramatta players Reni Maitua and Willie Tonga, was minor.

"He should be fine," Rennie said of Williams making his first appearance in Chiefs colours after making the move from the Crusaders.

"We gave him last week off to concentrate on his boxing but he has been running with the team."

However, Rennie, whose side are two from two in pre-season after notching a 38-36 victory over the fast-finishing Highlanders in Queenstown on Saturday, would not say what his plans were with regards to Williams and the Hurricanes match.

"We haven't made that decision," Rennie said.

The former Manawatu coach, in his first season with the Chiefs, said he was happy with the way Williams was balancing his rugby and boxing career.

"He wasn't knocked around too much was he," Rennie said of the fight between Williams and Tillman at the Claudelands Arena in Hamilton which was stopped in the first round.

"He's been fine. We've been conscious of the fact that he's been smashing himself at night in the boxing gym so we've taken him out of some of our conditioning stuff. He has been doing our skill-based work and he's got a pretty good idea of what we want to do."

The Chiefs travel to Taupo via Te Kuiti on Wednesday and are sure to pull the crowds at their various public training sessions along the way, as well as the match at Owen Delany Park on Friday.

There is no doubt that Williams will be a big drawcard this week and for the remainder of the season but it remains to be seen how much rugby he plays.

He has been hampered by knee and hamstring complaints during his short rugby career in New Zealand and is known to be reluctant to push through the pain barrier where injuries are concerned.

Williams is also allowed another fight this season, in accordance with his New Zealand Rugby Union contract.