Aaron Baddeley admits he's blown away to have notched a golfing milestone that even his childhood idol Greg Norman can't boast about.

Almost a quarter of a century after upstaging Norman to win the 1999 Australian Open as an amateur with a two-stroke victory over the Shark at Royal Sydney, Baddeley will on Thursday become only the sixth Australian to play 500 PGA Tour events.

"I just had no idea I was coming up to 500 events until last week and a friend told me about it," Baddeley said on a zoom call from California on Wednesday.

"It's pretty crazy. I can't say I ever thought about getting to that number but, once here sort of, it's pretty cool."

Even more cool considering Norman, the second-longest-serving world No.1 in history behind only Tiger Woods, only played 330 PGA tournaments.

"That's crazy. I thought he would have easily been on the list," Baddeley said.

But while Baddeley has Norman covered for longevity, the 42-year-old father of six concedes his career hasn't quite reached the heights he'd hoped for.

The sky seemed the limit after Baddeley successfully defended his Australian Open crown in 2000 to achieve the unique - and rather - spectacular double as an amateur and professional back-to-back winner of his national championship.

"I feel like I've little under-achieved. Definitely with the goals that I have set," he said ahead of the first round of the Fortinet Championship.

"My life-wise, I feel like I've exceeded all my expectations with my family, my kids. I couldn't be more at peace and joyful off the golf course.

"But golfing-wise, I definitely feel like I've underachieved.

"But, in saying that I feel, I feel like I've got a lot of my best years ahead of me.

"I feel like I set goals that I can still achieve and that's just not like a wishing thing."

Baddeley credits his golf-loving children for helping him maintain the drive.

"It's pretty easy to keep the fire stoked and wanting to get better," he said.

"There's definitely some days where I'll be like, 'Oh, I'll take the day off and then they're like, dad, can we play nine holes?'

"I'm like, 'Sure, let's go.'

"So that's a lot of fun to be able to do a lot of my play and practice with. I can't say I've ever really lost a passion for.

"Now even being 42 I feel like it's never difficult for me to go out and practice and to grind and to try and get better.

"The goal is to always improve, to always get more wins."

Chasing PGA Tour win No.5 in his 500th start, Baddeley is among seven Australians teeing up on Thursday, joining Cam Davis, Lucas Herbert, Harrison Endycott, Greg Chalmers, Cameron Percy and Geoff Ogilvy.

American world No.7 Max Homa is the defending champion, gunning for a rare tournament three-peat.

MOST APPEARANCES ON THE PGA TOUR BY AUSTRALIAN GOLFERS:

Steve Elkington - 565 (10 wins)

Stuart Appleby - 551 (9 wins)

Jim Ferrier - 528 (18 wins)

Robert Allenby - 525 (4 wins)

Bruce Crampton - 513 (14 wins)

Aaron Baddeley - 499 (4 wins)

David Graham - 410 (8 wins)

Adam Scott - 386 (14 wins)

Wayne Grady - 338 (2 wins)

Jason Day - 334 (13 wins)

Greg Norman - 330 (20 wins)

Craig Parry - 305 (2 wins).