Updated

Former world No. 1 Yani Tseng looks to be breaking out of her prolonged slump. She fired a 9-under 63 on Saturday to move three strokes clear of the field through 54 holes of the Safeway Classic.

Tseng, whose last tour win was in March 2012 at the Kia Classic, finished three rounds at 18-under-par 198. Her total of 198 set a new tournament record by one stroke.

Annika Sorenstam set the old mark of 199 in 2002, when the event was a three- round tournament.

Suzann Pettersen (70) and Pornanong Phatlum (71) share second place at 15- under-par 201.

World No. 2 Stacy Lewis fired a 65 to move into a tie for fourth at minus-14. She was joined there by Morgan Pressel (65), Anna Nordqvist (63) and Lizette Salas (68) at Columbia Edgewater Country Club.

Tseng, who has made 37 starts since her last win, birdied the first before running off three birdies in a row from the third. She followed a birdie on the par-5 seventh with a birdie at the eighth to give her six birdies in the first eight holes.

The 15-time LPGA Tour winner tripped to a bogey on the ninth. Tseng bounced back with a birdie on the 10th. She traded a bogey on the par-5 12th for a birdie at 13.

Tseng drained three birdies in a row from the 15th to soar three strokes clear of the field. She parred the last to end there.

"I just feel good about my swing. I went back to Taiwan the last two weeks to play golf with some young LPGA players in Taiwan, and they're really helping me to be back in this position, to be more excited to make birdies, to try to beat everybody out here," Tseng said.

"I feel I played a little more aggressively the last two days. It just feels like I tried to go for the pin every shot and tried to make birdie every hole. My coach from Taiwan, he's here with me this week, and I think that helps a little bit and keeps me very relaxed, and we had a great talk every round, and it's good."

Tseng didn't go into details, but insinuated she's had trouble on and off the course the last few years, and that's why she hasn't won since March 2012.

"It's a really long story, but really, I went through lots of things, and my life has been really tough, and it's not just about golf and outside of golf," Tseng explained. "But I feel like I've become more mature. I know I didn't have a great result, but as a person I feel like I learned so much with my family and friends and for my life and not just about golf.���I learned from this two years."

Pettersen stumbled to a bogey on the second, but came back with birdies at four and six. Around the turn, she birdied the 10th and 12th to move to 16- under, but she dropped another stroke on the 17th to end at minus-15.

Phatlum, the first-round leader, opened with a bogey at the first, but got that shot back as she birdied the third. She posted back-to-back birdies at the sixth and seventh to get to 16-under.

Over the final 11 holes Phatlum carded 10 pars and a bogey at the 17th to share second.

NOTES: Tseng owns the 54-hole lead for the 15th time in her career, and she has gone on to win 10 of the previous 14 ... Austin Ernst played as a single on Saturday and fired a 10-under 62 to tie Sorenstam's course record.