Tseng was a one-stroke victor Sunday at the RR Donnelley LPGA Founders Cup tournament in Phoenix. It was her 24th professional win and 14th in the last 15 months.
She has been ranked at the top of women's golf for 57 weeks. Only Lorena Ochoa (158 weeks) and Annika Sorenstam (60) were No. 1 longer.
Miyazato, who tied Choi for second in Phoenix, goes from ninth to No. 7 this week, with an average of 6.41. That forces Jiyai Shin (6.36) down one place to eighth and Stacey Lewis (6.18) down one to ninth. Brittany Lincicome (5.85) remains in the No. 10 spot.
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