South Koreans Ryu So-yeon and Park Sung-hyun and Canada’s Brooke Henderson are tied for the lead on six-under par after day two of the Women's PGA Championship in Chicago.
Overnight leader Park followed her first-round 66 by shooting a level-par 72 at Kemper Lakes Golf Club.
Ryu, celebrating her 28th birthday, and Henderson carded rounds of 69 and 71 respectively to make up the three-way tie.
On a day when temperatures reached the mid 30 degrees Celsius, Henderson hit four bogeys and five birdies.
"It was kind of up-and-down all day," she said.
"I would have liked to have shot a little bit better today, but one-under when it was so hot and so windy, I'll take it."
Spain's Carlota Ciganda is a shot back on five-under.
Two-time major winner Lydia Ko of New Zealand was the biggest mover, recovering from a first-round 74 yesterday to shoot a six-under 66 and put herself two shots off the lead.
Her round today matched the tournament’s lowest so far.
Ko is joined on four-under by the United States’ Annie Park and Thailand’s Moriya Jutanugarn.
A further shot back are Thailand’s Wichanee Meechai, Sweden’s Dani Holmqvist, Japan’s Nasa Hataoka and the US’s Jaye Marie Green.
England's Bronte Law is among a nine-strong pack tied in 12th place on two-under.
World number one Inbee Park of South Korea missed the cut at five-over.
Action in Chicago is due to continue tomorrow.