Lee is trying to become the first back-to-back champion since fellow Australian Karrie Webb achieved the feat in 2000 and 2001 and started with a bang at the iconic Californian course, posting two birdies from her first four holes.

But her approach to the par-5 6th hole left the World No.6 with plenty of work to do and she walked away with a bogey.

Lee made another birdie on the 10th, but dropped shots on the 12th and 16th to finish at even-par 72 in a tie for 20th, four behind leaders Hyo Joo Kim of South Korea and China's Xiyu "Janet" Lin.

"I kind of made a mistake on 6, the chip into the green, and I had a long putt and I made bogey, which is quite a soft mistake for me," Lee said.

"I was two-under at that point and went to one-under and I feel like a little bit of momentum kind of stopped there.

"At any par-5 you're looking to make birdies and with the opportunities that you have around this golf course, I know how tough it can get to have the birdie opportunities."

"Hopefully I can get my butt into gear and have a really good second day and the rest of the week." – Minjee Lee.

Although she has yet to win in 2023, the West Australian has been in the mix in her past five events, including a sudden-death play-off loss to World No.1 Jin Young Ko last month at the Cognizant Founders Cup in New Jersey.

Apart from the early round blip the 27-year-old felt her game was in good shape.

"I feel like my game is there, I just haven't quite had, I guess, the momentum and just everything come together to really produce a really low one, so hopefully I can get my butt into gear and have a really good second day and the rest of the week," Lee added.

Lee is spearheading a five-strong Australian charge that includes fellow major winner Hannah Green, Grace Kim, Gabriela Ruffels and amateur Maddison Hinson-Tolchard, who is playing her first major championship this week.

Kim opened with a two-over 74 while Ruffels and Hinson-Tolchard carded disappointing 78s top open their account.

Green, the 2019 KPMG Women's PGA champion, had a miserable back nine, adding three bogeys to sign for a 76.

World No.9 Lin has never won on the LPGA Tour but finished in joint third at the recent KPMG Women's PGA Championship two weeks ago, while eighth-ranked Kim won her only major title at the 2014 Evian Championship.

They held a one-shot lead over six players at three-under 69, including Irish pair Leona Maguire and 21-year-old amateur Aine Donegan, and American duo Allison Corpuz and Bailey Tardy.

The third major of the women's golf season is offering up a record $A16.5 million purse, with $A3 million to the winner, but Pebble Beach was tough going for some of the world's best.

Top-ranked Ko (79) bombed to leave the Korean tied for 125th, while World No.2 American Nelly Korda was at four-over.

Exciting young American Rose Zhang, who won in her professional debut last month, posted a two-over 74 to sit joint-39th.