Ryu So-yeon captured the US Women\'s Open on Monday by rolling in two birdies in a three-hole aggregate playoff to edge South Korean compatriot Seo Hee-kyung. It was the first major title for Ryu who forced the playoff with a birdie on the final hole of regulation in the weather-plagued tournament at the Broadmoor course. \"Unbelievable,\" said Ryu, who is the fifth South Korean to capture the US Women\'s Open. \"I can\'t believe it.\" After darkness halted the fourth round play on Sunday, Ryu returned Monday morning needing a birdie over the last three holes to force a playoff with Seo. Seo finished a day earlier at three-under 281. Ryu made the birdie on No. 18, then began the playoff 30 minutes later. Both players parred the first playoff hole and then on No. 17 Seo hit into a sand trap on the right side of the fairway. She finished the hole with a bogey. Ryu put her drive on 17 down the middle of fairway and went on to birdie the hole for a two-stroke advantage. Ryu hit her approach to four feet on No. 18 for an easy putt and her second birdie. \"I did my best. I did everything I could,\" said tour rookie Seo. \"She (Ryu) did a great job.\" Ryu is also the fourth South Korean to win the event in the last seven years as 10 of the top 14 players this year were from Asia. South Korea icon Se Ri Pak followed the two rising Korean stars on the course during Monday\'s playoff. \"I\'m proud of it,\" Ryu said. \"To see my hero, Se Ri Pak, out there fighting for me. It\'s pretty powerful, yeah.\" Seo said this would give her confidence going forward. \"Finally I can trust myself now,\" Seo said. \"I am looking forward to next season. We have lots of tournaments in Europe and Asia.\" Defending champ Paula Creamer closed with a 75 to finish in a tie for 15th. World No. 1 Tseng Yani of Taiwan, who was seeking to become the youngest golfer in history to complete a career grand slam, finished in a tie for 17th.