PORTLAND, Ore. -- Yani Tseng, formerly the No. 1 women's golfer in the world, recaptured that form on Saturday with a 9-under-par 63 that gave her a three-shot lead going into the final round of the LPGA Safeway Classic.
Tseng made 11 birdies at Columbia Edgewater Country Club during the round and was at 18-under 198 after 54 holes.
Suzann Pettersen, who carded a third-round 70, and Pornanong Phatlum (71) were tied for second at 201.
Four players -- world No. 2 Stacy Lewis, Morgan Pressel, Anna Nordqvist and Lizette Salas - were at 202.
Nordqvist fired a 63, Lewis and Pressel each shot 65 and Salas had a 68.
Lewis posted her best round of the week. She hasn't made a bogey on the 6,545-yard layout.
"I don't know if I've gotten this far in a tournament" without one, she said.
Lewis said she thought about that while standing over a 15-foot putt to save par on No. 14. And some friendly trees on the par-4 18th not only kept her hybrid tee shot from possibly going out of bounds but also sent her ball back onto the fairway, helping her quest for a fourth victory of the LPGA season.
Tseng, is looking for her first tour win since 2012. The 2011 player of the year has been in a slump and ranks 33rd on the 2013 LPGA money list. She had missed four consecutive cuts before tying for 24th at last week's Canadian Women's Open.
Both of her top-10 finishes this season came at the start of the year. It has been 36 starts since her last victory.
"It's great to be back in (contending) position again," she said. "I was really happy out there. The galleries are awesome and I just love every part of the golf out there and really enjoyed every shot.
"I just feel good about my swing. I played a little more aggressively the last two days, tried to go for the pin every shot and make birdie every hole."
One of her bogeys came after a snap-hook off the tee on the par-5 12th. She said bouncing back with a 12-foot birdie putt on the par-3 13th was a key.
Phatlum led after the first two rounds.
"My putting was not really good today," she said.
Pettersen also stalled, managing to play the final six holes in par, with a bogey on the 17th.
"It wasn't that good of a round for me," she said. "I felt like the greens were a lot more bumpy coming in (in the last group), but I'm just really glad there's one more day because there's still another low round in me."
Another group of four players -- Karrie Webb, Sandra Changkija, Cristie Kerr and Caroline Masson -- were 13 under through three rounds.
Austin Ernst, a tour rookie from LSU, turned in a 62 that put her among three players at 12 under.
Ernst said her "goal score today was 64." She shot 29 on the front nine and "made a ton of putts," including "every putt I looked at except for I think two."
She bogeyed the 11th after having to punch out from the rough with her second shot. And on the back nine, "I had two putts I just rolled over the edge," she said.
Tseng felt the pressure when she was on top of the world rankings.
"Everybody expects you to win every week, but it's impossible," Tseng said. "But I felt like I would be winning every week. I try, but it's really hard."
Pettersen said she was happy to see Tseng having success again.
"There's no one that I'd rather see playing better and playing well again than Yani," Pettersen said. "I know she's been through a very rough patch. Like I said to her, she's just got to stay patient. She's too good not to kind of hang tough and be in the game."
Tseng and Pettersen are paired in Sunday's final twosome, and Tseng said she figures it will take a strong finish to claim the trophy.
"I think you need a low round (Sunday) to win at this course," Tseng said. "You can see how strong the LPGA is right now. You don't know who's going to shoot 10 under tomorrow to win the tournament."
"This whole tournament is a shootout," she said. "Whoever wins tomorrow is probably going to shoot 65 or better."