Defending champion Frederike Kanhler and her partner Melanie Gernert were forced to show nerve in their 21-19, 22-20, 15-13 loseto Russian duo Maria Braktova and Evgenia Ukolova in a match followed with close attention.

Their counterparts of the German men's teams, Jonathan Erdmann/Stefan Windscheif and defending champions Sebastian Fuchs/Thomas Kaczmarek, however, have set up Sunday's semifinal clashes respectively with Italian Paolo/Matteo Ingrosso and Polish Grzegorz Fijalek/Mariusz Prudel.

Ukolova admitted that the quarterfinal against the German duo was a very though one.

"It was a very difficult match. First, due to the sun, that complicated deeply our volleyball, but mainly because of the good performance of our opponents, which were very strong," she said.

"Of course we will continue to maintain our goal for the championship, which is to secure the gold medal.

"My partner and I play very well together; we help each other a lot and we are gaining more confidence," she added.

Braktova and Ukolova, who still had not lost any set in the event, will next face Poland's Katarzyna Urban and Joanna Wiatr in the semis, while Czech Marketa Kolocova/Krystina Slukova to play Spain's Elsa Baquerizo and Liliana Fernandez Steiner.

The women's and men's finals are also scheduled Sunday, for 1600pm and 1700pm local time respectively.