Cameron Smith has fought back tears describing his worst day as a pro golfer, the local favourite shooting a 7-over-par 78 to miss the cut in his Australian PGA Championship defence.

While fellow Aussies Min Woo Lee and Adam Scott are separated by just a stroke atop the leaderboard and primed for a title shootout, three-time event champion Smith will have the weekend off to ponder what went wrong in Brisbane.

He began Friday 10 shots off the lead at Royal Queensland but slid further behind.

A double bogey at 10 and bogeys on the final two holes lowered him to 9-over for the tournament, well behind the projected cut line of par and 21 shots behind leader Lee in equal 147th place.

The former world number two and Open Championship winner said he could not remember a worse day on the golf course as a pro.

“Yeah, no words. Shit,” Smith said while choking back tears.

“I’ve performed under pressure before and it’s not acceptable, a bit upsetting actually.

“I know what I’m doing, it’s just going out there and committing to something is another thing.”

Smith missed putts, sprayed drives, found bunkers and again left irons short, shaking his head at what is believed to be his worst round in tournament golf.

Min Woo Lee speaks to Cameron Smith as they walk the course at the Australian PGA Championship golf tournament.

Smith’s horror day came as playing partner Min Woo Lee (right) enjoyed a stellar round to take the outright lead.(Getty Images: Andy Cheung)

Good showings in Brisbane and at Sydney’s Australian Open next week were crucial for Smith, who as a LIV Golf member has limited chances to boost his world ranking and earn selection for next year’s Paris Olympic Games.

Smith finished second in the LIV Golf season that concluded a month ago and was also runner-up in his only other appearance since, at this month’s Hong Kong Open.

“I hope I can get it together for next week and put on a better show than that,” he said, before spending the next 15 minutes signing autographs and posing for photos with fans.

Meanwhile, Lee (66) and Scott (65) traded birdies to move clear at the top

“It’s golf, that happens and next week I’m sure he’s going to bounce back, it’s what good players do,” Lee said of Smith.

“With family and friends, in his hometown … a few drinks and loosen up for next week.”

A dialled-in Scott was unlucky not to have gone even lower after an eagle approach and hole-in-one effort on par fours both bobbled out.

John Lyras had a par on the 18th to card a round of 67 and back up his opening-day 65 to be outright third at 10-under, while an ace on the 17th party hole helped Curtis Luck (67) to 8-under and a share for fourth with Lucas Herbert (68).

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AAP

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