UPDATE, Friday, May 18: With her 6-2, 6-3 win over Caroline Garcia in Rome, Simona Halep will retain the No. 1 ranking next week and be seeded first at Roland Garros. The win also puts Halep into the semifinals of Rome against Maria Sharapova, who defeated 2017 French Open champion Jelena Ostapenko, 6-7 (6), 6-4, 7-5.

From the AP:

Sharapova required more than three hours to eliminate last year's French Open winner, Jelena Ostapenko, 6-7 (6), 6-4, 7-5; and defending champion Elina Svitolina defeated Angelique Kerber 6-4, 6-4 for her sixth straight victory over the former No. 1 player.

Svitolina will next face 26th-ranked Anett Kontaveit of Estonia, who beat Australian Open champion Caroline Wozniacki 6-3, 6-1.

Sharapova's semifinal opponent will be either top-ranked Simona Halep or Caroline Garcia.

ROME (AP) — In the women's tournament, Simona Halep's hold on the No. 1 ranking received a boost when American Madison Keys withdrew from their last-16 match due to a rib injury.

Halep now needs to progress further than No. 2 Caroline Wozniacki to stay in top spot.

Wozniacki beat 15th-seeded Anastasija Sevastova 6-2, 5-7, 6-3 and next faces Anett Kontaveit, who ousted 1999 champion Venus Williams 6-2, 7-6 (3) for her second win over the American in two weeks.

Last year, Halep rolled her ankle in the final and lost a lead and the championship to Elina Svitolina.

Halep next plays seventh-seeded Caroline Garcia.

Svitolina overcame a poor start to beat 14th-seeded Daria Kasatkina 0-6, 6-3, 6-2. She'll now face former No. 1 Angelique Kerber, who routed Maria Sakkari of Greece 6-1, 6-1.

This is the last major warmup for the French Open, which starts in 10 days.

Jelena Ostapenko, preparing to defend her title at Roland Garros, rallied past Johanna Konta 2-6, 6-3, 6-4 and will meet three-time Rome champion Maria Sharapova, who eliminated Daria Gavrilova 6-3, 6-4.