Reigning US Women's Open champion So Yeon Ryu of South Korea was ousted 2-up by American Vicky Hurst on Saturday in a quarter-final at the LPGA Sybase Match-Play Championship.
World No. 13 Ryu, an LPGA rookie seeking her first triumph since her major victory last year, lost after a third round that saw World No. 1 Yani Tseng of Taiwan and World No. 2 Na Yeon Choi of South Korea eliminated.
"We both played pretty solid the whole day," Hurst said. "She kind of let it go at the end, but it was pretty close."
Sunday's semi-finals for the $1.5 million event send 37th-ranked Hurst against Taiwan's Candie Kung and American Morgan Pressel facing Spain's Azahara Munoz. Winners play Sunday afternoon for the title at Hamilton Farm Golf Club.
Kung, the lowest-ranked of the last four at 49th, ousted Tseng 3 and 2 to reach the last eight then outlasted Paraguay's 41st-ranked Julieta Granada 2 and 1 to stay in contention for her first title since 2008.
Pressel, seeking her first LPGA triumph in more than four years, took out Sweden's Anna Nordqvist 5 and 4 to book a semi-final date with Munoz, who eliminated American Stacy Lewis by the same score.
"This afternoon I had a little bit of a break and didn't need to make quite as many birdies, but tomorrow I'm going to need to make the birdies again because I'm sure 'Atha' is going to come out strong."
Pressel, who turns 24 on Wednesday, has not won an LPGA title since the 2008 Kapalua Classic. She won the 2007 Kraft Nabisco crown to become the youngest major winner in LPGA history.
"I definitely want to win again and I'll have a chance tomorrow," Pressel said. "No matter what happens, this is the best I've played in a long time. I'm going to give it everything I have tomorrow."
Ryu seized the lead three times early against Hurst only to have the American square the match each time. Hurst took her first lead with a par at the par-4 15th, then birdied the par-3 16th for a 2-up lead.
Ryu birdied the 17th to create the only quarter-final that reached the 18th hole, but Hurst parred the last to win the hole and secure the triumph.
Granada and Kung were all square through 14 holes, Kung having taken the lead three times and Granada having answered within two holes each time. But Kung won the 15th with a birdie and the 16th with a par before they each parred the 17th to hand Kung the triumph.
World No. 15 Pressel, who eliminated Choi in 19 holes in round three, was not pushed so greatly in her quarter-final.
Pressel won the par-3 third when Nordqvist bogeyed, took the par-5 fifth with a birdie and captured the par-4 seventh on another bogey from the Swede.
After they exchanged the first two holes on the back nine, Pressel birdied the par-3 12th and par-4 13th then matched Nordqvist's par at 14 to end the match.
Munoz, ranked 19th, ousted the highest-seeded player in the last eight by dispatching sixth-ranked Lewis, who won at Mobile last month.
The Spaniard eagled the par-5 second hole and won the par-3 third and par-4 seventh and ninth all after bogeys by Lewis. Munoz birdied the 11th to go 5-up before Lewis won her only hole with a birdie at 12.
Munoz, 24, won the 13th with a par and halved the 14th with a par to advance to a match against her friend Pressel.
"We both want to win bad, so I think it's going to be fun," Munoz said. "I wish I wasn't playing her to be honest."
Tseng's ouster was the top upset early, but no shock to her after a tough week.
"I wasn't surprised. I lost because I played bad this week," Tseng said. "But it's disappointing. I like match play but I just couldn't get it in the hole."
Kung went 3-up after seven holes, Tseng won back-to-back holes before Kung began the back nine with a birdie to win the 10th. Tseng won the 13th with a par to pull within 1-down, but Kung birdied 15 and 16 to close out the match.