Playing in the first group of the day from the 10thtee, Tabuena produced the hottest of starts at the hybrid event, posting birdies on nine of his first 10 holes, including the first seven holes, to open up a huge lead.

At that stage he looked certain to break the Lake Karrinyup Country Club course record of 63 set by James Morrison during the 2014 Perth International.

But as the cameras started scrambling to focus on Tabuena, his game started to wobble.

The birdies dried up, and two bogeys in his final eight holes meant he was forced to settle for a seven-under 65 and share of the lead alongside Norway's Kristoffer Reitan, who posted eight birdies and a bogey in a strong opening round.

Reitan managed to tie Tabuena after he dropped multiple shots coming home. PHOTO: Paul Kane/Getty Images.

“It feels great. It's certainly not new, but it's something I can't get used to,” Tabuena said of being atop the leaderboard. “I love coming to Perth and it feels like home. The weather's similar, the courses are similar, and it's great to be back. Shooting seven-under on Thursday is not a bad score, except my alarm this morning was 3:30 in the morning. But it paid off and I'm pretty happy with my position.”

But Tabuena couldn't help but wonder what could have been if his hot early form had kept going.

“I started to force shots that I wasn't comfy with,” Tabuena said.

“I started to go at pins when I shouldn't have, and the bogey on the par-three (5thhole) cost me.”

LEADERBOARD

For his part, European Tour rookie Reitan took his good play as another learning experience.

“It's pretty good, yeah, I'm enjoying it,” he said of playing on the world’s second biggest circuit. “I'm just trying to learn every week. Even if I play really bad, I'm trying to learn something, and if I play well, it might be because I've learned something. So I'm just trying to learn as much as I can from every tournament and try to unlock my best golf.”

Sitting behind Tabuena and Reitan are Kiwi Ben Campbell and Englishman Richard McEvoy, who are equal third after five-under rounds of 67.

A shot further back, Australians Nick Flanagan and Brad Kennedy are among a big group of players at four-under, with Kennedy reaching six-under at one time before a bogey and double bogey over his last two holes cost him second on his own, while Flannagan was happy with his round having battled a back injury in recent weeks.

“It got pretty average again the last couple of days,” Flanagan said.

“I had some work done here, and just (been) keeping up with the stretches I've been doing.

“Like first thing in the morning it gets really, really tight and I've kind of got to nurse it for 20, 30 minutes.

“I've got to take some anti-inflammatories and then do all these pretzel stretches slowly, because usually when it goes it's from quick movements of rotation.”

Rising star Min Woo Lee and fellow local Jason Scrivener settled for two-under 70s alongside tournament favourite Thomas Pieters, with the first of two cuts to be made at the conclusion of the second round tomorrow. Before the final 24 advance to the six hole match play on Sunday.

-Additional reporting Jimmy Emanuel