Choi finished tied for third at the CN Canadian Women's Open and moved from fourth to No. 3 in the rankings while Park used a runner-up finish in British Columbia to climb from 11th to No. 9.
They both finished behind 15-year-old Lydia Ko, a South Korean golfer who lives in New Zealand. Ko had just one round last week of more than 68 in winning the Canadian Open by three strokes.
Earlier this year she won on the Australia Ladies tour to go along with victories at the Australian Women's Amateur Golf Championship and the U.S. Women's Amateur. Those make her the No. 1 amateur women's player in the world; the win at the Canadian Open pushes her to No. 45 in the overall rankings.
At 15, she is the youngest winner ever in an LPGA event.
Yani Tseng is still on top of the rankings. She has a ranking points average of 14.32. Stacy Lewis, who tied for sixth at the Canadian Open, is second with an average of 8.54, just ahead of Choi (8.52) while Feng Shanshan slips to No. 4 at 8.36.
Ai Miyazato (7.58) comes in at No. 5 ahead of Suzann Pettersen (7.22).
The rest of the Top 10 is bunched together. Amy Yang takes the seventh spot with 6.40 while Ahn Sun-ju, up one place this week to eighth, is at 6.31 and Park has an average of 6.21. Cristie Kerr, who drops two places this week, is at 6.11 and Mika Miyazato goes from 10th to No. 11 at 6.00.