It ended four days of match play in which Wie had been dominant. And it sent her off to this week's U.S. Women's Open near Boston, without the victory she had in her grasp as late as the 33rd hole.

"Nothing really worked out for me today from start to finish. I just played terribly," Wie said. "I think I played the worst that I've played all week. I only made four birdies, and I made a lot of bogeys, and I gave a lot of strokes away."

No gift stroke was greater than her three-putt on the 34th hole. Wie, who trailed only three times in six matches, was 2 down after six holes in the morning 18 of the scheduled 36-hole final.

She rallied to lead 4 up through the 14th hole, but Tseng whittled her deficit to 2 at the lunch break.

"Even though I was 2 up, I felt like I was 5 down," Wie said. "I think she had a lot of grind in the second round. I tried to think it was a new round, but I had a lot of pressure on me. I don't know. I just didn't function."

Tseng finally brought the match all square with a birdie on the 31st hole, but she handed the advantage back to Wie with a poor tee shot that led to a bogey on the 33rd and dropped to 1 down.

"I did not panic because I still had three holes to make that (up)," Tseng said.

Said Wie, "I felt that it was good momentum for me, and it was my fault that I didn't carry that to the next hole. I just made a horrible three-putt."

After Tseng two-putted for par, Wie missed a 3-footer for par. They halved the 35th hole with pars. After good tee shots on the par-5 final hole, both went for the green on their second shots and found bunkers.

Wie had a long sand shot from the left side and left herself a 24-foot, uphill putt. From the front bunker, Tseng blasted to 12 feet. Wie's putt for birdie drifted just to the right of the cup. Tseng then rapped her putt dead center.

"I got a little bit tired at the end," Wie said. "I couldn't keep my concentration level up. I just had a hard time putting. That was the main problem, and I couldn't get anything close to the hole."

Despite the disappointing loss, Wie said she will take a stronger mental attitude (because of more experience) and improved shot-making skills into the U.S. Women's Open.

"Like I said a couple of days ago, I've learned how to shape my ball (working with David Leadbetter). I did that really well today," she said. "I've learned how to make the putts when I need to make the putts. I've learned how to swing easy and put it in the fairway. I got a lot of my game plan done, and I think that this week will help me in the long term."

Wie's coach, Gary Gilchrist, who walked every hole with her throughout the grueling six-day event, said the loss would be valuable for Wie, who is well into her grooming for a professional career.

"It's going to teach her to hang in, which she did to the end, and over time, she's going to have to understand that there's ups and downs in the game of golf," he said. "She got beaten by a pretty good putt."

For Tseng, a 15-year-old from Taiwan who has spent the past four summers in the U.S. competing, the victory was the biggest of her young career.

"I'm not really intimidated by Michelle," Tseng said through her U.S. host and chaperone Ernie Huang. "There's a couple of reasons. One is I look at myself as a long hitter, too. And second is my friends who happen also to play in this tournament watched Michelle play and they told me, 'You're going to do fine, and you are just as good.' So I start to build up my confidence by not being intimidated.

"I've always wanted to play with Michelle. Once the match-play tree came out, I was excited because I would have an opportunity to play with Michelle. ... I know Michelle probably was going to make the final, and I was excited that we were not on the same bracket, so (there was) no chance being eliminated early on. ... So it ended up a wonderful opportunity."

Wie was scheduled to play a practice round today at the site of the U.S. Women's Open, the Orchards Golf Club in South Hadley, Mass.