Michelle Wie and Jiyai Shin shared more than the top of the leaderboard after the third round at the CN Canadian Women's Open.
Both players suffered plenty of mosquito bites after a rainy round that saw them finish tied at 10 under for the tournament at St. Charles Country Club.
"Actually, they tried to kill me," laughed Shin, who wiped out Wie's three-stroke lead with a 3-under 69.
Wie, who recorded three birdies to go along with three bogeys in her even-par round, agreed with her South Korean playing partner.
The native of Hawaii said the winged nuisances affected her game.
"I have to say of everything, the mosquitoes were the hardest to concentrate," Wie said. "They were pretty bad. But I found out they were a little better on the greens than on the fairways.
"They were very bad on the rough, so I'll try to avoid that tomorrow."
"I used the (mosquito) spray, but I feel like they (got) worse," said Choi, who posted a 71.
"I think they like the smell."
Pettersen, the defending champion ranked No. 3 on the World Rolex Rankings, shot a 72.
"Today was just awful for me," Pettersen said. "But I'm in reach of the top so it was a good day to play bad and hang in there."
Three Canadians are part of the 73-player field looking for a share of the $2.25 million purse, with $337,500 going to the winner.
Charlottetown's Lorie Kane was the low Canadian after posting a morning round of 4-under 68 that had her even for the tournament and tied for 26th.
Montreal's Lisa Meldrum was 2 over and tied for 41st following a round of 71, while Adrienne White (75) of Red Deer was 4 over in a tie for 53rd.
Kane was smiling after rebounding from a 75 on Thursday and a 73 on Friday.
The 15-year veteran's third round featured spells of light rain and the ever-present mosquitoes.
"Being from Prince Edward Island, we can get some pretty nasty ones, too," Kane said with a laugh when asked if the bugs were the biggest she'd ever seen.
But these, I gave quite a bit of blood today."
No Canadian has won the event — the only LPGA Tour stop in Canada — since Jocelyne Bourassa in 1973.
Wie, ranked No. 12 in the world, is seeking her first victory this season and second of her career.
The 20-year-old joined the tour last season and won last year's Lorena Ochoa Invitational. The Open is her 15th event of the season and her highest finish was third in May's Tres Marias Championship.
No. 4-ranked Shin also joined the tour last year. The 22-year-old already has three victories, including last month's Evian Masters. She's also posted nine top-10 finishes this season.
Shin and Wie will play together Sunday for the fourth straight round this week.
"Tomorrow should be a fun game because right now Michelle, she has (been playing great)," Shin said. "And then also I have a good feeling, too."
Rachel Hetherington of Australia had the lowest round of the day — and her season — with a 66.
One player who wasn't feeling great Saturday was No. 8-ranked Paula Creamer of the U.S., but mosquito bites weren't to blame.
Aside from playing with a thumb injury, Creamer began suffering from what she believed was food poisoning in the morning.
She saw a doctor and had a shot before her round and another at the turn.
"This was the hardest thing I've had to do," said Creamer, who still recorded a 70 and was tied for ninth at 4 under with fellow American Morgan Pressel.
"I've played through a lot of pain and I've played through being sick a bunch, but this was a hard one. The weather didn't help much, either."