Kremlin Cup finalist Zvonareva ceded 8th place to Williams as the American won the Zurich Open in Switzerland on Sunday.
Russia's Dinara Safina, 22, retained her second position, which she reached last week to become only the fourth Russian woman to make the top two since the rankings started 33 years ago.
Russia's Olympic gold medalist Elena Dementieva and her compatriots Maria Sharapova and Svetlana Kuznetsova also stayed steady, ranked fifth, sixth and seventh, respectively.
Serbia's Jelena Jankovic, who won the Kremlin Cup tournament in Moscow two weeks ago, still tops the rankings.
Women's Tennis Association rankings top 10:
1 (1) Jelena Jankovic (Serbia)
2 (2) Dinara Safina (Russia)
3 (3) Serena Williams (U.S.)
4 (4) Ana Ivanovic (Serbia)
5 (5) Elena Dementieva (Russia)
6 (6) Maria Sharapova (Russia)
7 (7) Svetlana Kuznetsova (Russia)
8 (9) Venus Williams (U.S.)
9 (8) Vera Zvonareva (Russia)
10 (10) Radwanska Agnieszka (Poland)
