The 21-year-old star from Taiwan took advantage of the short, 472-yard, par-5 final hole by hitting an 8-iron to within 20 feet with her second shot. She rolled in the eagle putt to finish her round, doubling her cushion over Australian Katherine Hull.

“I played really well again,’’ said Tseng, who is at 12 under and has just one bogey through 54 holes. “I really enjoyed the big crowd out there. They clap on every shot and I showed them my big smile all the way around.’’

Hull played a flawless third round, including five straight birdies to finish with a 66.

“A great way to finish. I’ll always remember this round,’’ Hull said.

The Australian made only one birdie on the way out, at the long sixth, when she hit a pitching wedge to within 3 feet. Four straight pars on the back nine followed, before a 5-iron to within 6 feet on the short 15th started her run of birdies.

She followed with a gap wedge to within 12 feet for birdie at No. 15, and a 5-iron to 20 feet the following hole. She got up and down out of a bunker at 17, then two-putted from the back of the green for another birdie on the short, par-5 finishing hole.

“It will be exciting going out in the final pairing in a major for the first time tomorrow,’’ said Hull. “It’s what we all work hard for. It’s my first time being in this position but I’m going to treat it like any other day and just go out there and do my best.

South Korean In-Kyung Kim moved into third place at 6 under with a 68. She picked up three birdies on the front side, dropped a shot at the 10th, then got it back at the 16th. Her roller coaster round included another bogey at No. 17, but an eagle at 18 left her smiling.

Birdies at the last two holes moved American Brittany Lincicome into fourth place at 5 under, and there were five players another stroke back.

Cristie Kerr’s even-par 72 put her alongside fellow American Christina Kim, after Kim finished birdie-eagle on the closing holes. Norway’s Suzann Pettersen, South Korea’s Hee-Kyung Seo, and Japan’s Momoko Ueda also are in the group at 4 under.

PGA — At White Sulphur Springs, W.Va., Jeff Overton overcame a tough start to shoot 4-under 66 for a three-stroke lead entering the final round of the inaugural Greenbrier Classic.

Overton made five birdies on the back nine of the Old White course to move to 18 under.

The second-round leader kept the lead despite a pair of others flirting with 59. D.A. Points three-putted the par-5 17th for bogey, finished with a 61, and is alone in second at 15 under, and J.B. Holmes couldn’t convert a 10-footer for eagle at No. 17 and shot 60.

Boo Weekley shot a 67 to reach 13 under, and Holmes is in a four-way tie for fourth with Jonathan Byrd (64), Brendon de Jonge (65), and Jimmy Walker (67) at 12 under.

Holmes was among 17 players who made the 36-hole cut on the number.

Double heart transplant recipient Erik Compton, seeking his first top-10 PGA Tour finish, is among three players at 11 under.

Champions — Fred Couples shot a 5-under 65 for a share of the US Senior Open lead, feeding off a raucous hometown crowd in Sammamish, Wash., hoping the native son can win his first USGA championship.

Couples matched Bernhard Langer (68) at 5 under at tree-lined Sahalee Country Club, with Langer birdieing the final hole to pull even. They are the only players under par after three rounds.

Couples shot a 4-under 31 on the front nine, making birdies at Nos. 2, 5, 7, and 9, and holing a bunker shot on the sixth for par. He added a birdie at the 16th to post the best round of the week.

Langer had a streak of 20 holes without a bogey snapped at the 12th, but he rebounded with the birdie at No. 18.

Couples and Langer were five shots clear of Chien Soon Lu (68) and Tom Kite (69). Peter Senior (68), Michael Allen (71), Tommy Armour III (72), and John Cook (72) were 1 over.

European — Ross Fisher of England will take a one-shot lead into the final round of the Irish Open after shooting an even-par 71 in Killarney.

Fisher built a five-shot lead after opening his third round with four birdies in his first seven holes. But after putting his approach shot into the water on the par-4 eighth, Fisher made double bogey and dropped two more shots late in his round to finish at 12 under.

That gave renewed hope to his playing partner, Francesco Molinari, who at one point was six strokes off the lead. Molinari shot a 69 to finish one behind Fisher. Another stroke back is Spain’s Gonzalo Fernandez-Castano, who shot a 3-under 68.