STRASBOURG, France (AP) — Fourth-seeded Carla Suarez Navarro beat American Christina McHale in straight sets on Tuesday to reach the quarterfinals of the Strasbourg International.

The Spaniard, who won 6-4, 6-1, is the highest-seeded player left in the tournament after top-seeded Caroline Wozniacki withdrew on Monday because of back trouble and No. 2 Elena Vesnina lost her first-round match. Third-seeded Mirjana Lucic-Baroni pulled out before the tournament started.

Suarez-Navarro will meet Samantha Stosur in the quarterfinals after the Australian swept past Madison Brengle of the United States 6-0, 6-1.

Shuai Peng of China is also safely through after beating Amandine Hesse of France 7-5, 6-2, but ninth-seeded Monica Puig is out after losing 6-2, 6-3 to Kristyna Pliskova of the Czech Republic.