Lewis, who was the outright leader in the first two rounds, survived a double-bogey on the 15th hole to finish at 1-over 73 for the round and an 11-under 205 for the LPGA tournament.
Saturday's 73 was 10 strokes over the 63 she fired in Thursday's opening round. She was 2-under on Saturday before hitting a rough patch that included bogeys on the 12th and 14th holes and a double-bogey on 15. Her birdie on 18 kept her from slipping into second.
Park was 2-under Saturday. She also had two bogeys on the back nine and birdie on 18.
Benedict Cumberbatch's dramatic reading of R. Kelly lyrics is just what you need
Exploding whale video goes viral on Internet