Suzann Pettersen shot a 4-under 68 to take the U.S. Women's Open lead at 5 under, and Michelle Wie made a big move to get into contention Friday at Blackwolf Run.
Wie had a 66 to close within a stroke of the lead. Cristie Kerr, the 2007 Open winner, also is a stroke behind Pettersen going into the third round Saturday.
Sandra Gal, Inbee Park and Vicky Hurst shot 70 to reach 3 under.
Kerr, who shared the first-round lead at 3 under with Lizette Salas and Brittany Lincicome, shot a 71. Salas had a 73 and is 2 under for the tournament.
Lincicome had a miserable day, shooting an 80 and falling to 5 over.