(CNN) -- South Korea's In-Kyung Kim had the Kraft Nabisco golf tournament at Mission Hills in California all but won on the final hole Sunday -- all she needed to do was tap in for par from about a foot out and she was virtually guaranteed the win.
But her putt rimmed out for a bogey forcing a sudden death playoff that she lost on the first hole.
Her compatriot Yoo Sun-young rolled in a 15-feet birdie to take the first women's major of the year.
"I'm speechless right now. I played pretty solid today," the 25-year-old Yoo said in a television interview by the green.
Her win was in stark contrast to Kim's heartbreaking loss. After sinking the putt, she covered her ears with her hands and looked skyward in despair before going back to the 18th tee for the play-off. Both players were tied at nine-under-par 279 after 72 holes.
Yoo easily took the play-off after Kim drove her ball deep into the left rough.
"I didn't think about winning today because I didn't want to expect too much, and I didn't want to let myself down," Yoo told reporters after becoming the second South Korean to win the event, following Grace Park in 2004.
Yoo climbed five places to 16th in the world rankings after claiming her second victory on the LPGA Tour, having also triumphed at the 2010 Sybase Match Play Championship.
Kim has won three times on the LPGA Tour, but is still waiting for her first major title.
"Sometimes things happen, and it's kind of tough because it's the Nabisco, and hopefully I'll have better or more chances," the 23-year-old said.
World No. 1 Yani Tseng had begun the day tied for the lead with Sweden's Karin Sjodin, but narrowly missed going to the the playoff when she missed a long birdie putt at the 18th hole to finish one shot behind the leaders.
"I was totally shocked that I couldn't make that," said the 23-year-old from Taiwan, who was seeking to become the youngest player to win six major titles.
"But I tried my best again. I finished strong. It was a day I really don't want, but I gave my 100% effort out there."
Tseng also led going into the final round of last year's tournament, but finished three shots behind Stacy Lewis.
"Last year when I finished I was crying so hard, but this year I was happy, smiling, enjoy the crowd, enjoy walking on the 18 holes, and I think it's because I do my best every shot," she said.
"And I said maybe God just wanted another player to win and give me something to learn more and improve myself."
On Saturday, Sjodin fired a four-under 68 to join Tseng on nine-under at the top of the leaderboard. However, she eventually tied for fourth at 281 with Lewis (66) and Koreans Amy Yang (69) and Seo Hee-kyung (71).
She was unable to hold her three-shot lead gained early in the final round after an eagle at the second hole, while Seo took a three-shot edge in the back nine before sliding back.