At the end of the game he approached both teams as they put together a united huddle to cheer "hippray hippray hippray!" to each other and told them how impressed he was at William's sporting attitude.
But as Pirates coach David Taukamo pointed out to Mr O'Keefe and other impressed locals, it wasn't just William.
"It's the whole team - that's how we play it."
It is a philosophy toward rugby Mr Taukamo has promoted since he began coaching with Pirates about three years ago.
"We always take that approach and it doesn't matter who we play.
"You don't diss the other side at any time - I teach the team to be humble and even when you are winning by a big margin you can't take the game away from the other side because they have given it their best."
Mr Taukamo said his young players had taken his approach on board and it now came naturally to them.
"It is about having a good attitude - that is the main thing," Mr Taukamo said.
It was also reflected in their approach to training and giving it their best sporting shot as they had yet to lose a game.
William's mum Valerie said she was proud of the way her son, and his teammates, approached the game and gave their opponents credit, and support, out on the field. "Yes, people do say it is unusual but that's the way they play it."
William said the score really did not come into it when giving the opposition praise.
"If it was three-all I still would - it's sportsmanship."
He has been playing since he was 5 and was following in older brother Ben's playing footsteps - Ben plays for Napier Boy's High School and both had been sparked by their dad Brent's advice and support through the years.
His No1 ambition? "To be an All Black."
Asked who his favourite player was, he asked, "Can I have four?".
He rates Israel Dagg, Dan Carter, Richie McCaw and the No3 prop (of course) Owen Franks.
"I reckon we'll be unbeaten this season," he said. "But even if we lose one it doesn't matter - it's only a game."