PORTLAND, Ore. — Suzann Pettersen won the Safeway Classic for the second time in three years Sunday, taking advantage of playing partner Yani Tseng’s final-round collapse at Columbia Edgewater.

Three strokes behind leader Tseng entering the round, the third-ranked Pettersen closed with a 5-under 67 for a two-stroke victory over second-ranked Stacy Lewis.

Pettersen finished at 20-under 268 for her 12th LPGA Tour victory. The 32-year-old Norwegian also won the LPGA Lotte in Hawaii in April and won a Ladies European Tour event in March in China. She won the 2011 tournament at Pumpkin Ridge.

Tseng followed her third-round 63 with a 78 to tie for ninth at 12 under. The Taiwanese star, a 15-time winner on the tour who had a 109-week run at No. 1 in the world ranking, is winless in 37 events since the Kia Classic in March 2012.

Lewis, a three-time winner this year, shot a 68. Lizette Salas was third at 17 under after a 69, and 2008 champion Cristie Kerr was another stroke back after a 69.

A 72-hole event for the time, the tournament returned to Columbia Edgewater after four years at Pumpkin Ridge. Columbia Edgewater also was the tournament site from 1990-2008.

After a double-bogey on the par-3 second hole, Pettersen birdied five of the next six holes and eight of 11. The European Solheim Cup player made an 18-foot birdie putt at the par-3 eighth to overtake Lewis for the lead, curled in a 5-footer for birdie on the par-5 10th and made a 25-footer from off the green on the par-4 11th.

Pettersen opened up a four-stroke lead with an 8-foot birdie putt on the par-3 13th. She ran into trouble at the 175-yard, par-3 16th, following a short tee shot with a poor chip. But she minimized the damage when her next chip rolled within 3 feet to set up a bogey-saving putt. She then closed with two pars.

PORTLAND, Ore. — Yani Tseng moved into position to end a long victory drought, shooting a 9-under 63 on Saturday to take a three-stroke lead into the final round of the Safeway Classic.

Tseng, the 24-year-old Taiwanese star who has 15 LPGA Tour titles and had a 109-week run at No. 1 in the world ranking, is winless in 36 events since the Kia Classic in March 2012. She has tumbled to No. 15 in the world and missed cuts in the four of her last five tournaments.

After opening with rounds of 67 and 68, Tseng had 11 birdies and two bogeys Saturday in warm, dry and calm conditions to reach 18 under at Columbia Edgewater.

Tseng birdied six of the first eight holes and dropped a stroke on the par-4 ninth to make the turn in 5-under 31. She birdied No. 10, then hooked her second shot up against a restroom en route to a bogey on the par-5 12th.

Tseng rebounded with a birdie at 13, and added birdies at 15, 16 and 17 — all with putts of less than 10 feet to take the lead. She squandered a chance for another birdie when she missed a 5-foot putt on the par-4 18th.

Norway’s Suzann Pettersen, the 2011 tournament winner at Pumpkin Ridge, was tied for second with Thailand’s Pornanong Phatlum. Pettersen had a 70, and Phatlum, the leader after each of the first two rounds, shot 71.

Sweden’s Anna Nordqvist also had a 63 to join U.S. Solheim Cup opponents Stacy Lewis, Morgan Pressel and Lizette Salas at 14 under. Lewis and Pressel shot 65, and Salas had a 68.

Austin Ernst shot a 62 to tie the tournament record set by Annika Sorenstam in 2002.

Ernst set the stage as the first player on the course. Playing by herself, the tour rookie birdied eight of her first 10 holes to flirt with a 59, then bogeyed the par-4 11th. She is 12 under overall.

A 72-hole event for the time, the tournament is back at Columbia Edgewater after four years at Pumpkin Ridge. Columbia Edgewater also was the tournament site from 1990-2008.