After opening with rounds of 68 and 65 to take a one-stroke lead, Song had six birdies and a bogey to hold off her challengers.
SHIMA, Japan (AP) -- South Korea's Bo Bae Song won the Mizuno Classic on Sunday for her first LPGA Tour title, closing with a 4-under 68 for a three-stroke victory over top-ranked Lorena Ochoa, Brittany Lang and Hee Young Park.
"Honestly I couldn't sleep last night because I was so nervous," said Song, the Japan Women's Open winner last month at Abiko. "I went to bed at 11 last night, but woke up around 3. Usually that doesn't happen."
The 23-year-old Song finished at 15-under 201 at Kintetsu Kashikojima and earned $210,000 in the event co-sanctioned by the Japan LPGA.
She's comfortable on the Japanese tour, making it difficult to decide if she'll accept an LPGA Tour exemption.
"I don't know yet," said Song, also the 2008 Daikin Orchid winner in Japan. "I've played in several big tournaments when I lived in Korea, but I felt that Japan suits me more. So I still don't know yet. I've been playing in Japan for three years, and if I were to go to the U.S. tour, it's all a new start for me, so ..."
Ochoa shot a bogey-free 64, and Lang and Park had 68s.
"Now, I can go home happily," said Ochoa, set to begin play Thursday in her own Lorena Ochoa Invitational in Guadalajara.
"I just thought about doing my best today. I played aggressively."
Jiyai Shin, the 2008 winner who is trying to hold off Ochoa in the player of the year points race, closed with a 69 to tie for fifth with Yani Tseng (67), Mi-Jeong Jeon (69) and Inbee Park (69) at 11 under.
After opening with rounds of 68 and 65 to take a one-stroke lead, Song had six birdies and a bogey - on the par-4 14th - to hold off Ochoa and the other challengers.
"It wasn't only her," Song said. "A lot of the other players were chasing up, and I felt nervous. Mistakes are inevitable in golf, so I tried to play my golf to have little mistakes as possible."