Sei Young Kim of South Korea eagled the 15th hole for a 5-under 68 Friday to take a one-shot lead after the second round of the KPMG Women's PGA Championship, the second major of the season.
Kim overtook Hall of Famer Karrie Webb, who birdied the 18th for a 71. Two-time defending champion Inbee Park (68) joined Webb a stroke back.
The 22-year-old Kim, a two-time winner this season on the LPGA Tour, shot bogey-free golf to finish at 8-under 138 at the Westchester Country Club.
Suzann Pettersen rallied with seven birdies for the best round of the day at 66 and tied Canadian teenager Brooke Henderson (73) at 6 under.
Overnight leader Jenny Shin (75) and third-ranked Stacy Lewis (71) were three shots behind the leader.
The tournament, run by the PGA of America for the first time, is the second of the LPGA Tour's five major championships.