New Zealand international netball player Maria Tutaia was among the first to express her condolences.
"Condolences to the Halaifonua family, his partner and kids. May god give u all the strength in the world to get u thru this tough time.''
A friend of the family previously described him to the Herald as "very humble''. He reportedly lost a lot of weight a few years ago and got back into rugby, something he and his family loved.
"He's a really good guy, Big Willie,'' the friend said. "That's what we called him back in school. He lost heaps of weight over the years and became a family man.
"He loves his family and especially his kids. That's all he used to talk to me about - his kids.''
North Harbour Rugby Union Brett Hollister previously said the injury was the result of a single clash of heads with a Massey player with one minute remaining in the match.
"There was one collision at the very end of the game that he was involved in,'' Mr Hollister said.
"He was checked by the physio. The other player left the field and about a minute later the game ended. It was only then when the two teams were shaking hands that he collapsed.''