The next highest Spanish player in the list, Carla Suarez Navarro, dropped two spots to world No. 26, just 13 points ahead of Williams.
Further down the rankings, Alize Cornet of France jumped 14 places to world No. 34 after winning the Swiss Open on Sunday.
The current WTA rankings and point scores are as follows:
1. Simona Halep (Romania) 7,571 points
2. Caroline Wozniacki (Denmark) 6,740
3. Sloane Stephens (US) 5,463
4. Angelique Kerber (Germany) 5,305
5. Elina Svitolina (Ukraine) 5,020
6. Caroline Garcia (France) 4,730
7. Garbiñe Muguruza (Spain) 4,620
8. Petra Kvitova (Czech Republic) 4,550
9. Karolina Pliskova (Czech Republic) 4,485
10. Julia Goerges (Germany) 3,980
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)