Choi continued her solid play at the Twineagles Golf Club, recording only one bogey and breaking 70 for the third straight round. She is the only player in the field with three sub-70 rounds. Her 54-hole total of 12-under 204 is one stroke better than second-round leader Ai Miyazato, whose round Saturday was considerably more turbulent.
After a stellar 64 on Friday, Miyazato opened with a double-bogey 7 on the second hole and was 3 over after just five holes Saturday. Four back-nine birdies, though, moved her name back up the leaderboard and after carding a 1-under 71, she will begin Sunday within a shot of Choi.
Having clinched Rookie of the Year honors for 2012, So Yeon Ryu enters the final round in third place, two behind Choi. Her 4-under 68 on Saturday featured a stretch of four straight birdies from holes 5-8 and matched Beatriz Recari for the best round of the day.
After battling a back injury earlier in the week, Brittany Lincicome fired a 2-under 70 and sits in fourth place at 9 under, four shots behind the leader as she seeks her first win of 2012. There she is tied by France's Karine Icher, who matched Lincicome with a 70 on Saturday.
The day after giving her Player of the Year acceptance speech, Stacy Lewis shot a second consecutive even-par 72 and will begin the final round in a tie for 24th, 10 shots off the pace.