Ruffels in the major mix while red-hot Korda threatens

While world No.1 Nelly Korda is in the hunt for a stunning fifth straight victory, rising Australian star Gabriela Ruffels has made an impressive start at the Chevron Championship, the first women's golf major of the year.

American Lauren Coughlin posted a bogey-free six-under-par 66 on Thursday (Friday AEDT) to take the early lead at The Club at Carlton Woods in Texas, but white-hot Korda was joint second, just two strokes behind.

Celebrating her 24th birthday, Ruffels shot a three-under 69 to be in a share of fifth position and the leading Australian in a nine-player contingent.

Next among the Australians are Sarah Kemp (70), Steph Kyriacou and Karis Davidson (72) and Robyn Choi (73).

Former major winners Minjee Lee (74) and Hannah Green (77) have some work to do.

Ruffels, who is now ranked world No.84 after being outside the top 200 a year ago, has a strong record at this major, finishing in the top 25 three times when it was based at Mission Hills in California before shifting to The Woodlands a year ago.

"This tournament has always been really special to me. I have had great memories from this tournament and hopefully I can have a good one this week too," she said.

"It's my birthday today so I was happy to have a good round - it felt super solid."

Starting her day on the 10th, the Victorian quickly moved to three-under with birdies on three of her first six holes, before handing back shots with back-to-back bogeys on 16 and 17.

After another birdie on the 18th, Ruffels' second nine was less of a roller-coaster ride, with a bogey on the third offset by birdies on the sixth and ninth.

Coughlin, a 31-year-old ranked No.94 in the world, has only three top-10 finishes in her LPGA career.

With her husband on the bag this week, Coughlin started the tournament birdie-birdie at Nos.10 and 11 and wound up carding three birdies on each side in the windy conditions.

Coughlin was asked who she saw as her main competition entering this week.

"I mean, Nelly, of course," Coughlin said. "She's everybody's competition."

Korda is trying to win her second major after claiming the Women's PGA Championship in 2021, and join Nancy Lopez (1978) and Annika Sorenstam (2004-05) as the only women to win five consecutive LPGA events.

The 25-year-old birdied four of her final six holes to sit alongside compatriot Marina Alex and Japan's Minami Katsu.

Korda said she was battling fatigue from recent tournaments at the beginning of her round, opening with a bogey on the par-4 10th.

"I (could) definitely still feel maybe a little bit of tiredness, so it took me a while to get going," she said.

"I felt the nerves definitely at the start of the round. Once I made the turn, I was just playing free golf."

Lilia Vu, last year's champion, withdrew just before her tee time due to an ongoing back injury.

"Some days are better than others, and today was unfortunately not a good day," the American said in a statement on Instagram.

"During my normal warm-up routine, I had severe discomfort in my back and I felt that I could not compete up to my standards and made the decision to withdraw from the tournament ahead of my tee time."