After Williams was Svetlana Kuznetsova, who was ranked third last week. Maria Sharapova, another former No. 1, went from sixth to fifth, changing places with Elena Dementieva. Dinara Safina is seventh but only 565 ratings points behind Ivanovic.
Venus Williams held onto her No. 8 spot and Anna Chakveradze, who was 11th a week ago reentered the Top 10 at No. 9. Vera Zvonareva, the fifth Russian in the top 10, is 10th.
While the women's rankings saw some changes, the top 23 places in the men's rankings remained the same this week. Rafael Nadal, who officially took over the top spot last week, remained No. 1 followed by Roger Federer, Novak Djokovic, David Ferrer and Nikolay Davydenko.
The U.S. Open, the year's final Grand Slam event, opened Monday and continues through Sept. 7.