OHTSU, Japan (AP) _ Defending champion Ko Woo-soon of South Korea fired the day's best score, a 5-under-par 67, and vaulted into a four-shot lead today entering the final round of the U.S. LPGA Tour's final tournament of the season, the $700,000 Toray Japan Queens Cup.

Ko, who started the second round two shots off the pace, birdied the first two holes before carding the day's only bogey on the third hole. The South Korean then scattered four birdies.

Ko compiled an 8-under-par 136 over the 6,463-yard, par-72 Seta Golf Club's north course.

``I like this tournament. I had nice scores today as there are no winds like yesterday. I'm in top shape now so I'm confident of winning this tournament tomorrow,'' said Ko, who has won two tournaments on the Japan LPGA tour, but is winless this season.

Hiromi Kobayashi, seeking her third straight victory in Japan, also turned in a 67 for 140 along with Japanese compatriot Toshimi Kimura, who fired a 70.

``My shots became better after Beth (Daniel) checked my swing,'' said Kobayashi, who won the Fujitsu Ladies three weeks ago and took the Kibun Ladies two weeks ago.

Daniel fired a 72 for 143.

First-round leader Akiko Fukushima fired a 2-over-par 74 and dropped to 141 along with Jane Geddes and Nayoko Yoshikawa, who each shot 69s.

Another shot back at 142 were Liselotte Neumann of Sweden and four Americans, Colleen Walker, Jill Briles-Hinton, Michele Redman and Rosie Jones, as well as two South Koreans, Ku Ok-hee and Kim Ae-sook and Hisako Takeda.

Sweden's Annika Sorenstam, the U.S. LPGA's 1995 leading money winner, fired a 70 and was among six players at 144.

A field of 75 players at 7-over-par 151 or better advanced to the final round Sunday vying for a top prize of $105,000.

Americans Dottie Mochrie, with 152, and Alice Ritzman, 159, failed to make the cut.