Lewis won the Navistar LPGA Classic by two strokes, with Lexi Thompson coming in second. Lewis moves past Choi Yeon-na for the second place in the rankings, with Choi back to third.
Mika Miyazato moves up one place to ninth, switching places with Ahn Sujn-ju, who is 10th in the rankings, in the only other change in the women's Top 10.
The LPGA is off for two weeks in advance of a three-tournament swing through Asia that includes stops in Malaysia, South Korea and Taiwan.
Yani Tseng, who tied for 46th at the Navistar, still has a grip on the No. 1 ranking. Her rankings point average is 13.32, about 4.5 points ahead of Lewis (8.77) and a full 5 points up on Choi (8.32).
Feng Shanshan is fourth with an average of 7.94 with Jiyai Shin (7.83) at No. 5.
Ai Miyazato (7.30) comes in at No. 6 with Inbee Park seventh with an average of 7.17. Suzann Pettersen's average of 6.69 is worth the No. 8 spot. Mika Miyazato's average is 6.34 and Ahn's is 6.14.
Exploding whale video goes viral on Internet
Texas principal bans speaking Spanish, stirs controversy