Angelique Kerber had a 4-0 lead in the first set, but couldn't hold on against Karolina Pliskova.
Dennis Grombkowski/Getty Images

NUREMBERG, Germany (AP) - Karolina Pliskova of the Czech Republic upset top-seeded Angelique Kerber of Germany 7-6 (5), 6-4 on Thursday to advance to the semifinals of the Nuremberg Cup on Thursday.

Kerber squandered a 4-0 lead in losing the first set. Pliskova held her serve twice in the second, Kerber only once, and that decided the match.

Kerber is ranked No. 9 in the world, while Pliskova is No. 64.

In another upset, Karin Knapp of Italy outlasted seventh-seeded Caroline Garcia of France, 6-7 (9), 6-4, 6-4 to reach her first semifinal in 10 months.

Fourth-seeded Elina Svitolina of Ukraine downed Mona Barthel of France 6-4, 6-4 and will play Pliskova in the semifinals. Bouchard faces Knapp.

Copyright 2014 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

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