COLORADO SPRINGS, Colo. -- So Yeon Ryu birdied two of the three playoff holes Monday to defeat Hee Kyung Seo and win the U.S. Women's Open.
Ryu birdied the 18th in regulation to post a two-under 69 and join Seo at three-under-par 281. Seo completed her final round on Sunday with her second straight three-under 68 at the Broadmoor.
The 21-year-old Ryu played the three-hole aggregate playoff in 10 strokes, while Seo needed 13 shots. Ryu is the third-youngest winner in championship history.
"I won six Korean LPGA tournaments, but no majors, but now I won the U.S. Women's Open. I can't believe it," Ryu exclaimed in a television interview.
The duo started the extra session on the 16th. Both players two-putted for par on the par three.
Ryu drained an eight-foot birdie putt on the par-five 17th to grab a two-shot lead as Seo tripped to a bogey. Seo's drive stopped under the lip of a fairway bunker and she needed four shots just to reach the green. She two- putted for bogey from about 20 feet.
"On hole 17, I made a birdie and she made a bogey, so I had a little gap," Ryu explained in a Golf Channel interview. "I felt really comfortable."
Seo knocked her approach to the back fringe on the 18th, then two-putted from there for par.
"Nobody knows what is going to happen next, so I tried to prepare for today," Seo said in a televised interview. "I did my best, but So Yeon did a great job. I gave my everything."
Ryu knocked in a four-footer for birdie at the 18th to win by three strokes. The victory was Ryu's first on the LPGA Tour.
Asked in a television interview about having played the three playoff holes earlier on Monday, Ryu said, "It was good for me. All the pin positions were the same. It was a big benefit for me."
Cristie Kerr, the 2007 champion, was the only other player to finish in red figures at one-under-par 283 after closing out an even-par 71 on Monday.
The Monday finish was needed after five weather delays over the previous four days halted action for some 17 hours.
The third round was completed on Sunday, and nearly half the field finished their final rounds on Sunday as well. Seo put together two excellent rounds to get back into red figures.
Seo posted a pair of three-under 68s in the third and final rounds to go from three-over par after 36 holes to three-under par for the championship.
Ryu staged an impressive comeback as well. She stood eight strokes back with 28 holes left.
Maybe the biggest moment of the championship happened on Sunday.
Seo's group jogged off the 17th tee as they were falling behind the group in front of them. They were not being timed, but were asked to speed up their play. So after teeing off, the three players jogged down the 17th in an attempt to close the gap.
Seo narrowly missed her 20-foot birdie attempt, then lipped out her short par putt as well. That bogey allowed Ryu to force the extra session.
"I think the one mistake yesterday was on the 17th green," Seo said on TV of what her biggest error was.
With Seo on the range getting loose in case of a playoff Monday morning, Ryu got up and down for par from a bunker on No. 16. At the 17th, her birdie putt slid by the right edge.
Needing a birdie at the last to force the playoff, Ryu dropped her second shot within six feet. She calmly poured that putt in the middle of the hole for birdie.
Ryu then bested Seo in the playoff, which was the first on the LPGA Tour for both.
Angela Stanford finished off a one-over 72 on Monday to end alone in fourth at even-par 284. Mika Miyazato also shot 72 to take fifth at plus-one.
Two-time U.S. Women's Open winner Karrie Webb (71), 2008 champion Inbee Park (72) and Ai Miyazato (72) shared sixth place at two-over-par 286.
NOTES: Ryu collected $585,000 for the victory...Ryu became the fifth Korean winner of the U.S. Women's Open...Ryu is the third winner in the last four years of this championship to make this her first LPGA Tour title...This was the first all international playoff in the U.S. Women's Open and first all international playoff in a USGA event since 1988 when Gary Player beat Bob Charles at the U.S. Senior Open...Paula Creamer, the 2010 champion, stumbled to a four-over 75 in the final round to drop into a share of 15th at plus- six...After a week off, the LPGA Tour heads to France for the Evian Masters, where Jiyai Shin was a one-stroke winner last year.