Lee's triumph at the Scottish Open last Sunday, the biggest moment yet of the 22-year-old's career, caused emotional family celebrations back home in Perth.

"My parents and Minjee were up late, it was Monday for them – it was really awesome to get their reaction. Mum was crying and all that, it was an emotional night," Lee explained at the practice range at Royal St George's on Wednesday.

Dad Soonam and mum Clara Lee, who moved to Western Australia from South Korea a couple of decades ago, had stayed up late to watch the breakthrough triumph in a play-off in North Berwick which earned him a place in his debut major.

Instead of the quiet week off he'd been expecting, the victory has left him instead with a whirlwind few days at Sandwich, an experience he says he's so far found "awesome".

Early on Thursday morning, Lee will launch the 11-strong Australian challenge at The Open alongside his English pal Sam Horsfield, with whom he regularly plays 'Call of Duty', and South Africa's Christiaan Bezuidenhout.

"It just happened all so quick," said Lee. "I won that night and its like, 'now I'm in The Open', so it's turned around really quickly."

Talk about a surprise. Lee, considered hugely promising, had missed the cut four times in nine events on the European Tour while only earning a best finish of joint-17th.

"At this moment, I've got the bragging rights. We are a competitive pair, even though we don't get to see each other much. I mean, it's all love there – but there's a bit of competitive juices between our family. We're a sporting family."  Min Woo Lee

Yet with a starburst of a performance at The Renaissance Club, he reeled off rounds of 68, 69, 65 and 64 – including a career-best six straight birdies in the final round – and then beat Thomas Detry and Matt Fitzpatrick at the first extra hole.

It earned him a US$1.33 million (AU$1.78 million) winner's cheque and the chance to tease 25-year-old sister Minjee, a three-time winner on the LPGA Tour and currently the World No.15 woman player with whom he enjoys friendly sibling rivalry.

"At this moment, I've got the bragging rights," laughed Lee. "We are a competitive pair, even though we don't get to see each other much.

"I mean, it's all love there – but there's a bit of competitive juices between our family. We're a sporting family.

"My parents own a cafe now but mum used to be a pro golfer and dad was a swimming instructor."

As the older sibling, Minjee has been a guiding force for Lee but they learn from each other, he says. "We're very different personalities – she's a dead straight arrow and I'm all over the place.

"Her game's very steady, she's very level-headed, but she could learn a little bit off me too. Although I'm very up and down, sometimes you need that fire in the belly."

For when Lee is hot, he can be a birdie machine.

"I had 25 last week and six in the last round. I haven't done that before on Tour but I've always had a high birdie count so as long as I can keep those bogeys off the card this week, I should have a good chance."

It's a tough act to follow, mind. The last player to do the Scottish/Open double? A certain Phil Mickelson in 2013.

- Ian Chadband, Australian Associated Press