South Korean stars took advantage of relatively benign conditions in the first round of the Rio de Janeiro Olympic women's golf tournament on Wednesday.

Park In-bee and Kim Sei-young are tied for second at five-under 66 after the first day at the 6,245-yard Olympic Golf Course. Both players picked up five birdies against no bogeys to sit one behind the leader, Ariya Jutanugarn of Thailand.

Park, former world No. 1 who has dropped to No. 5 while struggling with injuries, said she couldn't remember the last time she had such a fine round.

"The wind didn't blow as much as it did during the practice round," Park said. "I am pleased to put in a good round at the Olympics, and I was able to regain confidence. Whether it was putting or ball-striking, my game was pretty solid overall. But there are still three rounds of golf to play."

Park, a seven-time LPGA major champion, said the thumb injury that has bothered her for months is behind her and she'd rather not discuss it.

While the players enjoyed a sunny weather Wednesday, more inclement conditions have been forecast over the next three days.

Park said while bad weather could wreak havoc on the players' minds, it wouldn't cause major issues because they're all used to playing in bad conditions.

Park missed just one fairway while hitting 15 greens in regulation.

Kim fared just as well statistically. She tied for the lead by hitting 16 greens in regulation, while hitting 11 of 13 fairways.

One of LPGA's longest hitters, Kim ranked fourth on Wednesday by averaging more than 273 yards off the tee.

"I didn't make a lot of mistakes today, and I think I had a perfect round, except for a couple of holes," Kim said of the fifth and 16th holes, where she made pars. "The greens were receptive today, and I had a lot of birdie opportunities. I was just trying to go for the center of the greens, and it worked out well."

Kim said the 10th, 12th and 15th are tough driving holes, and added, "If I can attack those three holes, then I think I should be able to post good scores over the next three rounds."

Chun In-gee, world No. 8, had a more up-and-down day, which included five birdies and four bogeys for a 70. She's tied for 19th.

Chun's opening birdie was quickly erased by three straight bogeys starting at the third. She then went birdie-bogey-birdie to make the turn at one-over par. She picked up two more birdies on the bogey-free back nine.

"I think I was a bit more nervous than I have been at regular tour events," she said. "I overcame three consecutive bogeys early to finish under par for the round. I think this will boost my confidence going into the next three rounds.

She was the first to tee off among the four South Koreans at

7:52 a.m. And with women's golf being contested at an Olympics for the first time since 1900, Chun said the significance of her first tee shot distracted her a bit.

"When I was making three straight bogeys, I felt like I couldn't concentrate," she added. "But I kept at it because I thought overcoming adversity would mean a lot."

Chun hit 10 of 13 fairways and hit 13 greens in regulation. She admitted she didn't hit the ball particularly well but added, "I've won 12 tournaments and only one or two of them were due to my ball-striking."

While Chun shrugged off her ball-striking issues, Yang said she would head right back to the range to address her problems.

"My shots didn't go the way I wanted to," Yang said. "I didn't hit a lot of fairways today, and left myself with tough second shots to greens. I barely saved pars on some holes."

Yang hit only eight of 13 fairways, and reached 10 greens in regulation.

"I went to one-under par with a birdie at the ninth, and that should have given me some life," she said. "Then I bogeyed the next two holes and never really recovered."

On a brighter note, Yang said she was pleased with her short game and putting. (Yonhap)