South Korean top seed Na Yeon Choi advanced to the semi-finals of the LPGA Match-Play Championship with two triumphs on Saturday but World No. 1 Yani Tseng lost in the quarter-finals. Taiwan\'s Tseng missed an eight-foot birdie putt on the 18th hole to give Norway\'s third-ranked Suzann Pettersen a 1-up triumph and a berth against Choi in Sunday\'s morning semi-finals ahead of an afternoon 18-hole final. \"It was do or die,\" Pettersen said. \"I feel good about my game and I will stick to my game plan on Sunday.\" Americans Cristie Kerr, the third seed, and Angela Stanford, last year\'s runner-up, reached the other semi-final after a pair of Saturday victories. Choi defeated Sweden\'s Sophie Gustafson 2 up in the quarter-finals while 18th seed Stanford ousted 10th-seeded compatriot Paula Creamer by the same score and Kerr vanquished Japanese fifth seed Ai Miyazato 3 and 2. Pettersen was 2-up on Tseng through six holes but birdies at the par-5 11th, par-4 13th and par-4 14th holes put the Asian star back on top. Bogeys by Tseng at 15 and 16 put Pettersen back on top but Tseng birdied 17 to level the match. \"I got off to a good start. I felt like I was in control until I was halfway down the back,\" Pettersen said. \"She gave me a few easy ones down the back. It comes down to who makes the putts at the end.\" On 18, Pettersen sank a testy 10-footer for her third winning birdie of the week at the 18th hole while Tseng was just left of the cup in her bid to force extra holes, losing in the round of eight for the second year in a row. \"It was a tough day,\" Tseng said. \"I just didn\'t make the putt at 18 and she won the match. You need to bring your A-game to stick around.\" Choi never trailed but saw a 3-up lead she built with birdies at nine and 10 trimmed thanks to bogeys at 11 and 15 before she sank a final birdie at 18 to close out Gustafson, the lowest-remaining seed at 42nd. Seeding were based upon last year\'s final LPGA money list. Creamer was 2-up on the 14th tee before Stanford battled back with birdies at 14 and 15 to square the match, another at 17 to seize command and a final one at 18 to complete Creamer\'s collapse. \"I just kept thinking, \'I\'ve got to make a birdie,\'\" Stanford said. \"I just had to tell myself, \'Keep rolling the ball. You\'ve done fine.\'\" Kerr birdied the seventh and ninth to make the turn 3-up, saw her lead trimmed by two shots when Miyazato birdied the 10th and 11th, then answered the challenge with birdies at 13 and 15 and a par at 16 to close out the Japanese star and book a date with Solheim Cup teammate Stanford. \"I\'ve never played Kerr head-to-head,\" Stanford said. \"I know she\'s a great putter. It should be a tough match.\" In earlier third-round matches, Kerr ousted South Korean Kyeong Bae 4 and 2, Stanford downed South Korean Meena Lee 5 and 4, Choi eliminated Canada\'s Alena Sharp 3 and 1 and Pettersen edged Stacy Lewis 1 up.