Chasing her fifth LPGA Tour victory of the year, Ai Miyazato shot a 5-under 67 on Saturday to take a three-stroke lead into the final round of the LPGA Safeway Classic.
The Japanese star was 11 under on Pumpkin Ridge's Ghost Creek Course.
Juli Inkster was tied for second at 8 under with Song-Hee Kim (64) and Na Yeon Choi (67) after an apparent 67, but the 50-year-old Hall of Famer was disqualified because she used a weighted training aid on her club to stay loose while waiting to make the turn at the 10th hole.
Miyazato has won four tournaments this season and is among five players in a tight battle for the No. 1 spot in the rankings. Cristie Kerr is currently No. 1, followed by Miyazato, Jiyai Shin, Suzann Pettersen and Yani Tseng.
About the only trouble Miyazato had was on the par-4 12th, where she hit over the green from a bunker. She muffed her shot and was still in the rough -- but she was able to hole it in from there to settle for a bogey.
"It went in, and it was really lucky, I think," she said, marveling that it wasn't worse.
Shin and Kerr were both in contention at 7 under. Kerr won the event in 2008 when it was played at Columbia Edgewater Golf Club near Portland International Airport. The tournament moved last year to Pumpkin Ridge, about a 20-minute drive from Portland in rural farmland near the base of the Cascade Range.
South Korea's Ji Young Oh shot a second-round 64 to top a group of four players at 6 under. She would have had the best round of her career had she not bogeyed the par-4 No. 18, but overall she was pleased.
"I had a good shot and a good putter," she said. "So everything was good."
Kim also shot a second-round 64. In her last 22 tournaments, Kim has 17 top-10 finishes.
"The first thing, the weather was perfect," she said. said. "And the course condition was pretty good, too."
Inkster was stern-faced and left the course quickly after learning of her disqualification. Later, she issued a brief statement.
"I had a 30-minute wait and I needed to loosen up," she said. "It had no effect on my game whatsoever, but it is what it is. I'm very disappointed."
Inkster broke rule 14-3, which says that a player cannot make a stroke or practice swing using a club with a weighted doughnut or any other training device or swing aid.
LPGA Director of Tournament Competitions Sue Witters said a viewer watching the television broadcast brought the violation to the attention of tournament officials.
Witters said officials did not become aware there was a problem until Inkster was already on the 17th hole. She was surprised when told, Witters said.
"Totally surprised," Witters said. "I mean, there was no malice there. Her sole reason for doing it was because she had been waiting 30 minutes and had to warm up."
M.J. Hur, the defending champion, was at 4 over and did not make the projected cut. The Safeway Classic is her first and only title to date.