The humble inside centre, who grew up supporting the All Blacks, said his grandparents were his biggest inspiration.
''I was so happy just to get the call and pull on the Wallabies jersey while my grandparents still have a chance to watch me," said Tapuai, who was born in Brisbane and raised in Melbourne.
"They've followed my whole career and one day they were hoping that I'd make the Wallabies.
''I'm very close to them. They raised me as much as my mum and dad, so it was pretty special to tell them I made the Wallabies. They're so excited. I just wanted to repay them for everything and make them proud. My parents are over the moon, too. This is for my whole family."
Tapuai was visiting his Melbourne-based family enjoying the last days of his holiday when Wallabies coach Robbie Deans called him.
''I definitely wasn't expecting this. I was just getting my parents lunch," Tapuai said.
''All I had planned for the summer was another pre-season back in Brisbane and Christmas with the family, so this is pretty special. I'll never forget this experience.
"This year was my first professional contract with the Reds and to win the Super Rugby title and get a Wallabies call-up, it just tops it off."
Tapuai played 10 matches for the Reds after three years in the Academy and finished the season as the starting No 12.
His finals form earned him an Australian Barbarians jumper and from there, the rest was up to the nuggety back who grew up idolising All Blacks Christian Cullen and Frank Bunce.
''I just took my opportunity like I had in the Super Rugby season and took it with both hands and knew if I did well I'd be a chance for further honours and well, I think it's paid off," said Tapuai, who is off contract with the Reds next year.
The former Australian Schoolboys and under-20s star was outside Berrick Barnes during that August match against Canada and is excited at the prospect of re-forming the partnership with the Waratahs playmaker, who will wear the No. 10 jersey for the two-match spring tour.
"It was different to Quade [Cooper], but I'm not going to be playing my whole life with Quade and it was good to learn off him," said the former Southport School scholarship student.
''Playing outside the likes of Quade and Will Genia just makes my game easier. You never know what Quade's going to do so you just learn on the run and that's something I learnt during the year, just expect everything and anything that comes at you. So that's what I did with Berrick. And if I get picked, it helps having played with him. I really enjoyed it in that Barbarians game. He's a great player."
Tapuai was almost in danger of being lost to Australian rugby, had it not been for an honest, hard look at his game last season. His ball skills and flair have always come naturally, but like Reds teammate Cooper and many other stars of the game, his defence was letting him down.
''I have always been natural at attacking but last year it was my defence that I kind of had to fix," said Tapuai, whose older brother John was a former Waratahs Academy player. "I worked at it during the pre-season last year and all this year. It was pretty hard to try and get onto it because I wasn't very strong at it, but I worked hard and it's paid off now."