BAD GASTEIN, Austria — Karin Knapp of Italy won two matches Friday to set up a semifinal against top-seeded Sara Errani at the Gastein Ladies.
Second-seeded Samantha Stosur takes on No. 7 Anna Karolina Schmiedlova of Slovakia in the other semifinal of the clay-court event.
In the quarterfinals, Knapp rallied from three games behind in both sets to defeat Polona Hercog of Slovenia 7-6 (5), 7-5. Hours before, Knapp beat Johanna Larsson of Sweden 6-3, 6-3 in a second-round match moved from Thursday because of thunder.
The 43rd-ranked Knapp, who is seeded third, hadn’t won a match since capturing her second career title in Nuremberg in May.
Earlier, Errani overcame neck problems to beat Russian qualifier Daria Kasatkina 6-3, 3-6, 6-2.
The 19th-ranked Italian received medical treatment while leading 4-3 in the opening set. She stuttered against her 151st-ranked opponent in the second set but dominated the third after two early breaks.
Stosur advanced to her second semifinal of the season by beating Danka Kovinic of Montenegro 6-3, 6-2. The Australian, who won her seventh career title in Strasbourg in May, avoided break points.
A week after winning in Bucharest, Schmiedlova kept her winning run going by defeating Annika Beck of Germany 6-2, 6-3.