Hong Kong - All Blacks star Sonny Bill Williams is "fighting fit" after recovering from a knee injury as he presses his Olympic bid at this week's Hong Kong sevens, his captain said on Tuesday.
The code-hopping Rugby World Cup-winner, who is now trying to bag Olympic gold, missed the last two world sevens series tournaments but appeared untroubled in training on Tuesday.
"He's fighting fit. He was disappointed to miss the last ones through a bit of injury and he's ready to go," captain Tim Mikkelson told reporters in Hong Kong.
Williams suffered a swollen knee before the Las Vegas sevens, with unconfirmed reports in New Zealand saying the problem was exacerbated by an economy-class long-haul flight to the United States.
Coach Gordon Tietjens was non-committal about the economy-class theory but he said Williams, 30, had been training hard before the problem flared.
"I really can't answer that," he said. "He'd just basically come off a pretty hard training week and it flared up so that's really what it was."
Williams, who has also enjoyed a distinguished rugby league career and has had success as a heavyweight boxer, showed no problems as he played a practice game and sprinted the length of the pitch in training.
"Sonny Bill Williams is fine. He loves the sport. He's a great athlete, he commits himself really well, he's got such a professional work ethic," Tietjens said.
"He's a great example for all the other younger players that are coming into the sevens environment and that's what's really special about him: he just sets high standards. It's great for the environment."
Despite his pedigree, Tietjens said even a player of Williams' standing needed tournaments and intense conditioning work to successfully switch to fast-moving, hard-running sevens.
"You just cannot make the transition in a short space of time," he said. "You've got to play world series tournaments.
"The game's evolved since the last time a lot of them would have played it. Even Sonny Bill Williams said the other day, this game's a different beast altogether. The conditioning levels are huge."
New Zealand, who won last month's inaugural Vancouver sevens, are hoping for another strong showing in Hong Kong, the highlight of the world series and regarded a dress rehearsal for the Olympic sevens in August.
After Hong Kong, the world series heads to Singapore, Paris and London before rugby makes its return to the Olympic Games in Rio after a 92-year absence.
"I've got players that are hungry to be an Olympian," Tietjens said.
"They all want to go to Rio, and every time they go out and they play in that black jersey, it's a performance they want to remember as about what puts them in that team to go to Rio.
"So that's why it's (Hong Kong) really important. We can't afford not to play well and the players can't afford not to play well."