Choi, despite a 3-hour delay on the final hole due to rain, birdied the par-5 18th for get to 14-under-par 202 after 54 holes. Lewis overcame two early bogeys in a 3-under 69 and holds a share of the lead. Choi is No. 2 in the women's world golf rankings and Lewis is No. 4.
Paula Creamer also had a 69 Saturday and is alone in third at 12-under. Ariya Jutanugarn, Danielle Kang, Azahara Munoz and Yoo Sun-young are tied for fourth at 9-under 207. Kang was 2-under 70 for the third round while Jutanugarn, Munoz and Yoo were all even for the day.
Jutanugarn was in the day's final group with Choi and Lewis at the 18th when rains hit, delaying play for about 3 hours. Jutanugarn, who had four bogeys and four birdies Saturday, ended the day with a par. Lewis also parred the hole and Choi had her lead-grabbing birdie.
Choi opened the day with birdies at Nos. 1 and 2 and took the lead with a birdie at the seventh hole. She added birdies at 10 and 14 before a bogey at the par-4 15th. The birdie at 18 left her at 67.
Lewis countered bogeys on the first and third holes with three straight birdies over Nos. 7-9. Second-nine birdies at 12 and 15 pulled her to 14-under for the tournament.