Safina returns to No. 1 world ranking

DAYTONA BEACH, Fla., Oct. 26 (UPI) -- Dinara Safina regained the world No. 1 women's tennis ranking and the Williams sisters both saw their ratings slip.

The WTA women's Top 10 underwent major changes -- only three players are ranked the same as they were last week -- with the tour starting its $4.6 million Sony Ericsson Championships Monday in Doha, Qatar.

Safina has been in a slump in which she has lost four of her last seven matches. That cost her the No. 1 ranking about a month ago but Monday she moved back ahead of Serena Williams, now at No. 2, by 155 ratings points.

Svetlana Kuznetsova retained the world No. 3 ranking but Caroline Wozniacki jumped two spots to a career-best No. 4. Elena Dementieva is again ranked No. 5.

Victoria Azarenka also improved two places and is ranked sixth in the world, which is a career mark for her. Venus Williams, with losses in two of her three matches since the U.S. Open, fell from fourth to seventh.

Jelena Jankovic, who sewed up the final spot at Doha last week, went from ninth to eighth with No. 9-ranked Vera Zvonareva just missing an invitation to Doha by five rankings points. Agnieszka Radwanska remained ranked No. 10 this week.