Bouchard, Kerber ousted in Antwerp

Antwerp, Belgium ( - Top seeds Genie Bouchard and Angelique Kerber were among Thursday's second-round upset victims at the Diamond Games tennis event.

German Mona Barthel upended the top-seeded 2014 Wimbledon runner-up Bouchard 4-6, 6-1, 6-2, while 34-year-old qualifier and former French Open champion Francesca Schiavone drilled the second-seeded German left-hander Kerber 6-1, 6-1 on the indoor hardcourts at Sportpaleis Merksem.

Bouchard has now dropped her last two matches, including a quarterfinal setback at the hands of Maria Sharapova at the Australian Open.

Meanwhile, nifty fifth-seeded Spaniard Carla Suarez Navarro came from behind in order to beat Romanian Monica Niculescu 4-6, 6-0, 6-2, fourth-seeded Czech Lucie Safarova leveled France's Kristina Mladenovic 6-4, 6-1 and sixth-seeded former Aussie Open runner-up Dominika Cibulkova of Slovakia held off Dutch qualifier Indy De Vroome 6-3, 3-6, 6-2.

Another Day 3 upset came when Czech Barbora Zahlavova Strycova subdued seventh-seeded Frenchwoman Alize Cornet 6-4, 6-2, while eighth-seeded Czech Karolina Pliskova avoided an upset by tackling German Annika Beck 6-3, 6-3.

Friday's quarterfinals will pit third-seeded German Andrea Petkovic against Cibulkova; Safarova versus Pliskova; Suarez Navarro against Schiavone; and Barthel versus Zahlavova Strycova. Petkovic saved eight match points in her second-round victory here on Wednesday.

The 2015 Antwerp champion will pocket $113,000.