"He was very good and competitive you couldn't beat him. At the news of his passing though his friend said 'you really beat me this time'," said Wainui's cousin Annie Gear.
"There was only one thing that would ever get him out of the water and it was the sound of Mr Whippy and that bell," joked Wainui's uncle Kevin Malloy.
"And when that bell went there was one person who was always going to be first to Mr Whippy and no one ever beat him and that was Sean.
"The world is a much better place for having Sean in it and all of our lives are much better lives for having Sean in them. Seany mate, I ask you just to always continue to smile on all of us."
The young father leaves behind his wife, Paige, and their children, Kawariki and Arahia.
"He was a star, he led the back three they called it 'bomb squad' so he could defuse those bombs. I was so proud of him, he took very ball and we're able to carry on and win the case because he inspired, he inspired us with his attributes on the field," a teary Cooper said.
Wainui was spotted by coach Cooper and signed with Taranaki at just 18 years old in 2014.
Wainui's siblings Whitney and Luke Wainui also spoke at his tangi.
"The four of us were extremely close and we held each other like the walls of a whare. You will be surely missed but always remain close to our hearts," Luke said.
Wainui's father Paul said his heart is starting to heal.
"I don't wish any parent to bury their own child especially this age, engari (but) God gives and God takes," he said.
The video of the tangi shared by Turanga FM Media finishes with an emotional performance of Paikea and Tika Tonu.
A Givealittle page set up by the Chiefs Rugby Club to support the family in Wainui's absence has climbed above $265,000.
A written statement from the Wainui whānau thanked everyone for their "love and generosity".
"The beautiful tributes that have come from those who loved him all across the world means a lot to us all.
"We understand there are many hurting right now and wanting to hear from the whānau, but please respect that we have just lost our baby brother, a son, a husband and a father and our focus right now is healing and laying my brother to rest.
"Thank you all again for respecting the whānau's wishes."
On Sunday morning the All Blacks paused the start of their haka ahead of this morning's test match against the USA in Washington DC to honour Wainui.
The haka stopped for 11 seconds before TJ Perenara began Ka Mate, to honour the 11 jersey worn by Wainui for the Maori All Blacks.
Six60 lead singer Matiu Walters sung the New Zealand national anthem while wearing a number 11 Maori All Blacks jersey.
