Strasbourg, France (SportsNetwork.com) - Former world No. 1 Jelena Jankovic and former U.S. Open champion Samantha Stosur secured berths in the quarterfinals at the Strasbourg International, a final clay-court French Open tune-up.

The second-seeded Serbian Jankovic took care of Chinese Zheng Saisai 6-3, 6-3, while the third-seeded Aussie Stosur received a walkover into the round of eight when Ukrainian Lesia Tsurenko pulled out of their scheduled second-round match at Strasbourg Tennis Club.

Also on Day 3, Sloane Stephens upended sixth-seeded fellow American Coco Vandeweghe 6-3, 6-4 and Croat Ajla Tomljanovic outlasted American Shelby Rogers 7-6 (8-6), 3-6, 6-2. Stephens will battle Jankovic on Thursday, while Tomljanovic will meet Stosur.

In some more second-round action on Wednesday, top-seeded American Madison Keys will face Croat Mirjana Lucic-Baroni and fourth-seeded French favorite Alize Cornet will take on Russian Elena Vesnina. Cornet titled here in 2013 and was the Strasbourg runner-up in 2012.