A special day for South Korea turned out to be even more special for Ryu So-yeon. Fighting her way into a tie at the end of 72 holes and then shutting the door on her rival, Ryu won the US Women's Open on Monday, defeating Seo Hee-kyung by three shots in a three-hole playoff. Ryu became the fifth South Korean to win the Open and the fourth in the last seven years. Ryu played the three-hole playoff in 2-under par, all but sealing it when she hit three perfect shots to the green on the par-5 17th for a birdie while Seo drove into a bunker and had to scramble for bogey. For good measure, Ryu hit her approach on 18 to four feet for another birdie. But really, it was the birdie she made on that hole about an hour earlier that set her up for the win. Trailing by one to an opponent who had closed out her round before darkness stopped play the previous night, Ryu hit a 6-iron uphill, over the lake on No. 18 to six feet. She slammed the putt home to pull into a tie and ended up with two birdies in an hour on a hole that yielded only 28 over five days.