Karlovic, Vesely reach Duesseldorf semifinals
Melzer is playing again after missing seven months with a shoulder injury.
The match between top-seeded Philipp Kohlschreiber of Germany and qualifier Mate Delic of Croatia was interrupted twice by rain and finally abandoned because of darkness, with Kohlschreiber leading 7-5, 4-4. Delic is in his first tour-level event.
Copyright 2014 by The Associated Press
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