The NRL is recognised as the toughest club competition in the world. While many other players have managed to achieve the feat, very few played from the cauldron of the front row.
Tamou moved from Levin to Sydney as a 13-year-old with his parents Dave and Pip and his career had been keenly supported by his New Zealand whānau since he made his NRL debut for North Queensland Cowboys in 2009.
Incredibly, he wasn't the only player to go from Nana's hallway to the big time. Younger cousin Kenny Edwards also played in the NRL, for Parramatta Eels, and still plays now professionally in the UK.
Both played junior rugby for Levin Wanderers and rugby league for Levin Knights as youngsters, appearing for the Knights' senior side in the Manawatū competition even though still in their early teens.
Tamou had always had huge support from Levin and his wider whānau, but possibly his biggest supporter was older brother Richie, who had never missed a test match in Australia and attended all of Tamou's 14 State of Origin games.
An avid sportsman himself in cricket, rugby and rugby league, he said his younger brother always had something special about him.
"He wasn't the type of player that would score 20 tries a game, but he had a good work ethic even way back then, just trying to improve, and he still has that today," he said.
"He's not afraid to train and do the hard work."
Richie said his brother was a humble family man and was grateful for the support that flooded in ahead of his 300th game.
There was a video montage sent over from New Zealand with messages from whānau, friends, and former coaches and players who had followed his career.
"He's pretty humble and keeps to himself and didn't really realise and was quite speechless and emotional when he saw all the message of support," he said.
Tamou and his wife Brittney live in Sydney and have four sons: Brooklyn, Bronx, Barclay and Boston. He said he felt lucky and fortunate to have so much support throughout his career.
"At first it was hard to fathom all the support ... why is everybody saying these nice things about me," he said.
"I'm happy to give my time to people and love hearing people say how nice and down to Earth I am because it's a reflection on my family, especially my mother.
"It's a standard of mine to be nice because I am a representative of all my family, and the best thing I love hearing is 'your mother did such a great job with you'."
Of the 300 games the 1.95m tall, 115kg, front rower played, 170 were for North Queensland Cowboys, 97 for Penrith Panthers and 33 for Wests Tigers.