ROCHESTER, N.Y. (AP) -- It's getting harder for first-time winners on the LPGA Tour to win again.

With all the global talent rushing in since the 1990s, one out of two golfers has failed to follow up a breakthrough win with another tournament triumph. Going back to 1950, when the tour was launched, the overall odds of repeating are far better -- just under 60 percent.

For Eun-Hee Ji, who opens her defense of the Wegmans LPGA on Thursday, a second win in her third year on tour would serve as "a validation." At least for now, however, Ji said she doesn't feel added pressure.

"I have already delivered the one win," the 23-year-old South Korean said through a translator. "Going from one to two? I feel better with this type of pressure than not winning a tournament at all."

The $2 million Wegmans LPGA has 18 of the season's top 20 money winners, including No. 1 Cristie Kerr. The field also features Anna Nordqvist, a 22-year-old rookie from Sweden who won this month's major, the McDonald's LPGA Championship, in only her fifth professional start. Also on hand are several top players, including Michelle Wie, Paula Creamer and Morgan Pressel, Laura Diaz, Helen Alfredsson, Pat Hurst, Wendy Ward and Nicole Castrale.

Absent are top-ranked Lorena Ochoa, who won here in 2005 and 2007, and the 2008 runner-up, Suzann Pettersen.

Already this year, three golfers have savored a second victory. In-Kyung Kim beat Hall of Famer Se Ri Pak by a stroke at the State Farm Classic on June 7. And South Korean compatriot Ji Young Oh, along with Yani Tseng of Taiwan, bagged their second career wins in May.

Winning one tournament puts a golfer in rare company: 269 women have landed on the all-time winner list since the 1950 Tampa Open, the tour's first sanctioned event.

The list of one-time winners, which currently stands at 110, has been around just as long: Polly Riley beat Louise Suggs by five strokes in Tampa, and never won again on the LPGA circuit.

One-timers still pushing for an elusive second title include Jackie Gallagher-Smith, whose sole success came in 1999, and Becky Iverson, who last scaled the heights in 1995. But hankering after further glory can quickly grab hold.

"I don't necessarily feel pressure, it's more that I really want to win one more time," Louise Friberg said before her maiden defense in March at the MasterCard Classic. "After your first win, you know how much fun it is and you know how good it tastes."

Since 1999, there have been 35 one-time winners and 34 previous winners who won again, so the decade-long odds of repeating are 49 percent. In the tour's 59 years, by contrast, 59 percent of winners have triumphed at least twice.

Heightened competition from abroad is a chief factor for the tightening odds, along with dominance by the likes of Annika Sorenstam, Karrie Webb, Se Ri Pak and, more recently, Lorena Ochoa. That quartet has notched 158 tournaments wins since 1995.

Last June, with a 5-under 67 in the final round, Ji overcame a three-shot deficit to beat Pettersen by two strokes at Locust Hill, a tricky, tree-lined course with compact greens in the Rochester suburb of Pittsford.

Ji sits 26th on the season's money list with $233,376. The best of her four top-10 finishes was a tie for sixth at this month's State Farm Classic.

"I got a new driver, and I modified my swing a little" this spring, said Ji, calling her accuracy off the tee and the fairway "the big strength of my game. And my weakness is my putting. Big problem!"

Winning on the LPGA Tour "boosted my confidence in my golf game," Ji said. "Now that I have one LPGA win under my belt, I don't really have the same type of anxiety or nervousness that I have to deliver right at that moment. It gives me the faith that because I've done it once, I can do it again."

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