BALTIMORE, July 24, 2014 (AFP) - Tseng's clutch putt gave her and Phoebe Yao a 1-up victory over world number one Stacy Lewis and Lexi Thompson after Teresa Lu and Candie Kung ripped Paula Creamer and Cristie Kerr 4 and 3.
"I feel like old Yani is back," the five-time major winner and former world number one said.
"I haven't had this feeling for a long time. I'm pumped up because I'm playing for my country."
The Americans, never led at any point in any match on day one of the showdown for global bragging rights between eight national teams of four women each.
"It wasn't like we played horrible," Creamer said. "But they made birdies and the putts they needed and we couldn't get anything to fall."
After three days of four-ball matches, singles matches Sunday will decide the $1.6 million event at 6,628-yard Caves Valley Golf Club.
But a US team boasting four of the world's top 12 players, as many as in the entire rest of the field, was in last place after being humbled 4-0 by Taiwan.
"I guess we learned those pairings don't work well," Lewis said. "But there are teams that could get zero points the next two days as well."
Tseng birdied three of the first six holes for a 2-up lead, missed a two-foot par putt at eight to surrender the hole, but Yao sank a clutch 12-foot birdie putt to halve 12 and a birdie to win the par-3 13th.
Lewis birdied 16 to square the match, only setting the stage for Tseng's winner.
"It certainly hurts to lose on the last hole because we hung in there all day," Lewis said.
Lu birdied the par-3 third, eagled the par-5 fourth, birdied the par-5 12th and birdied 15 to clinch the match.
"I don't know how (I did it) but the clubs were good," 44th-ranked Lu said.
Japan beat Sweden 3-1, the Europeans never leading in either match as Ai Miyazato and Sakura Yokomine beat Pernilla Lindberg and Mikaela Parmalid 2 up and Mika Miyazato and Mamiko Higa halved with Anna Nordqvist and Caroline Hedwall.
Nordqvist leveled with a birdie at 16 but she missed a five-foot birdie putt at 18 to win and Mika Miyazato made a four-foot par putt to halve the hole and match.
Yokomine and Ai Miyazato were never more than 2-up and the Swedes trimmed that edge three times, the last when Parmalid birdied 16, but Yokomine's closing birdie won.
"It was an amazing feeling but I was super nervous," Ai Miyazato said. "I had never played in that atmosphere."
- Mentally tough -
Australia and South Korea split as top world amateur Minjee Lee joined seven-time major winner Karrie Webb for a 2-up win over I.K. Kim and Choi Na-Yeon while four-time major winner Park In-Bee and Ryu So-Yeon beat Katherine Kirk and Lindsey Wright 3 and 2.
Lee birdied the fifth and sixth to put Australia ahead and the ninth and 10th for a 2-up edge. Kim birdied the par-5 12th only for Lee to birdie and win the par-3 13th. Choi birdied 15 to again close the gap but Lee sealed victory with a closing birdie.
"Minjee played great. I'm very proud of her," Webb said. "I just rode on her back."
"It was pretty awesome," Lee said. "She gave me a lot of advice on staying mentally tough."
Ryu won two of the first three holes with birdies and the Aussie duo never pulled level again.
"It was a really great experience," Ryu said. "It's kind of exciting and a little scary."
Spain defeated Thailand 3-1 as Azahara Munoz and Carlotta Ciganda beat Onnarin Sattayabanphot and Pornanong Phatlum 4 and 2 while Thai sisters Moriya and Ariya Jutanugarn halved with Belen Mozo and Beatriz Recari.
Scores from Thursday's opening four-ball matches at the inaugural LPGA International Crown team event (2 points for win, 1 for halved match):
Group A
Taiwan 4 United States 0
Candie Kung/Teresa Lu (TPE) bt Paula Creamer/Cristie Kerr (USA) 4 and 3
Tseng Yani/Phoebe Yao (TPE) bt Stacy Lewis/Lexi Thompson (USA) 1-up
Spain 3 Thailand 1
Carlota Ciganda/Azahara Munoz (ESP) bt Pornanong Phatlum/Onnarin Sattayabanphot (THA) 3 and 2
Ariya Jutanugarn/Moriya Jutanugarn (THA) and Belen Mozo/Beatriz Recari (ESP) halved
Group B
Japan 3 Sweden 1
Mamiko Higa/Mika Miyazato (JPN) and Caroline Hedwall/Anna Nordqvist (SWE) halved
Ai Miyazato/Sakura Yokomine (JPN) bt Pernilla Lindberg/Mikaela Parmlid 2-up
South Korea 2 Australia 2
Park In-Bee/Ryu So-Yeon (KOR) bt Katherine Kirk/Lindsey Wright (AUS) 3 and 2
Minjee Lee/Karrie Webb (AUS) bt Choi Na-Yeon/I.K. Kim 2-up
Standings (won, halved, lost, points)
Group A
Taiwan 2 0 0 4
Spain 1 1 0 3
Thailand 0 1 1 1
United States 0 0 2 0
Group B
Japan 1 1 0 3
South Korea 1 0 1 2
Australia 1 0 1 2
Sweden 0 1 1 1