THE imposing 121kg gamble, who the Wallabies have taken on tour to dethrone Eddie Jones and England, nearly ate himself out of a rugby career as a fast-food casualty in western Sydney.
It's rare for a Wallabies coach to select a player certain to miss half of a four-Test tour and almost unprecedented to put such faith in a rookie like Lukhan Tui.
Most of all, it's a measure of the explosive lift that the 21-year-old can offer from the bench with his bumping ball-carries, support play, the excellence in the air that helped beat the All Blacks and some thumping physical work.
Lock-flanker Tui has only earned three cameos off the bench in Tests and that is the role coach Michael Cheika has sized up for him on Saturday at Twickenham now that a hamstring niggle is coming right.
The Queensland Reds forward is still pinching himself at how far he's come so quickly to savour a win over the All Blacks in his third Test when it took Sean McMahon nearly three years as a Test player.
"That Bledisloe Cup Test was a big one for me and kind of personal being born in New Zealand and having my family there at the game," Tui said after a rehabilitation session in Cardiff this week.
"It made the win so much sweeter. It also made me think just how quickly things have moved."
Few know just how quickly because Tui only took his first unfit steps as a rugby player in 2014 after playing junior rugby league for Campbelltown Collegians in Sydney's far west.
Learning new skills wasn't the hard part. It was weaning himself of the fast food that was too tempting when he was working at KFC at Casula and Hungry Jacks at Campbelltown in his final years at John Edmondson High.
"I love food like any Polynesian but I got up to around 138kg in my teens and just had to get more strict on cutting out fast foods," said Tui, who could take on an 18-piece KFC family pack solo.
Former NSW Waratahs giant Will Skelton sorted him out with his first pair of decent rugby boots and gave him the wise counsel - "work hard and always eat well" - if he wanted to chase his dreams.
No team applies the blowtorch like the All Blacks and being dumped into the cauldron of a fluctuating Bledisloe Cup battle in Brisbane last month explained a lot about Tui's make-up.
When eight-year Wallabies stalwart Rob Simmons was stretchered off with a neck injury after 55 minutes, an unscarred cub with few miles on the clock was thrown into his sink-or-swim exam.
He ran with purpose and when the All Blacks put up the final kick-off with the Test still in the balance, he knew what was coming next.
"I grew up watching Bledisloe Tests and I knew straight away everything was on the line. So did Stephen Moore because 'Squeak' was the guy behind me who told me to be ready to get up for the ball at the kick-off," Tui said.
"It's always the same guy, Kieran Read, coming through so I was focused, maybe closed the eyes, and came down with the ball."
It was a clutch play and exactly what Cheika keeps urging from his new breed..
"Our biggest thing is getting a winning mindset for every moment of the game," Tui said.
"I'm pretty keen for this England game. I was playing under-20s in Manchester last year watching Wallabies-England on the TV so, like I said, it makes me think just how quickly things have moved."
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