Bonnie Doon’s Bautista (69 on Saturday) and Lennox Head’s Mackenzie (pictured) overhauled the 36-hole leader Josh Armstrong early to create a three-shot buffer by the end of the third round.

They are at 15-under par with Kiwi Ryan Chisnall (12-under) the nearest challenger entering Sunday’s climax.

Bautista played in the final group with Armstrong on Saturday and quickly jumped to the lead after Armstrong began with four bogeys in six holes on his way to a 75, closing with a four-putt on the difficult, multi-tiered 18th green.

Bautista, a 25-year-old from Sydney, has spent half his life in America where his father originates from. He has played at home in Australia all through this season with three top-10 finishes to show for his improved form.

He might have gone a deal lower on Saturday had he not made double-bogey at the par-4 14th hole after hitting his tee shot left and into the mulga, exacerbating the issue with a three-putt at the end. “My thought process was ‘I’m bogey-free until that point, so if I make double, that’s not really a bogey!’” he said later.

Mostly he was electrifying, lashing his drives and hitting the green at the 320-metre par-4 third hole, making eagle from short range.

Bautista’s individuality is worthy of note. Having won the NSW Junior championship and turning pro in 2018, he stunned the golfing community a year later when he walked away for two years, travelling to New Guinea, China, Japan, Thailand and Israel to volunteer with humanitarian aid organisations. Sunday could be a red-letter day for him.

“It would be my first major win in Australia, on this tour,” he said.

“It would be pretty cool. We show up here week-in, week-out because we want to win, so if I get a big win I’ll let myself celebrate and be happy if I do get it done. I look forward to tomorrow and working hard.”

Mackenzie, just 22, hails from the northern rivers of NSW and represented his state as a junior.

But he has had a difficult season with just one result of note, his tie for 12th at The National PGA Classic a couple of weeks ago. Significantly, it represented a change of momentum for the man from Ballina Golf Club.

“I had a horrible start to the year, had a few head problems with the golf swing,” he said. “Then I made my first cut of the year and slowly got a bit of confidence and slowly getting better and better.”

Mackenzie has won pro-am events but also is in search of his first four-round tournament win.

“I don’t know,” he said. “I’ll just go out there and have fun, see how it goes. We’ll see.”

As for Bautista, he knows that he will be on edge, but he’s happy to be that way.

“If I played golf and I wasn’t nervous, I probably wouldn’t enjoy it,” he said.

“It’s the nerves that are fun. You’re in contention. I’ll just show up and every single shot I’ll treat with the respect that it deserves and I’ll commit 100 per cent. I’ll try 100 per cent to shoot my best score and get to 20-under. That’d be a good goal, actually.”

The final round begins at 8.10am Sunday local time.

Television coverage is on Fox Sports and Kayo Sports from 12.30pm AEST.

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