Defending champion Barbora Zahlavova Strycova was sent packing in the quarterfinals Friday at the Bell Challenge tennis event.

Third-seeded German Mona Barthel drove out the sixth-seeded Czech Zahlavova Strycova 6-3, 6-4 in 1 hour, 26 minutes on the indoor carpet at PEPS Laval University. Zahlavova Strycova defeated New Zealand's Marina Erakovic in last year's Quebec City finale.

Barthel's semifinal opponent on Saturday will be Belgian Kirsten Flipkens, who was leading Anna Tatishvili 6-2, 3-0 when the Georgian retired from their bout. Flipkens upset top seed Dominika Cibulkova in the opening round.

In the night matches, eighth-seeded Lucie Hradecka and Kristina Mladenovic were both winners to set up the other semifinal match.

Hradecka of the Czech Republic took down American Lauren Davis 6-4, 6-2 while Mladenovic of France had an easy 6-0, 6-1 win against American Melanie Oudin.

The 2012 winner of this $220,000 tournament will collect $37,000.