BERLIN: Americans Jessica Pegula and Madison Keys lost to Victoria Azarenka and Liudmila Samsonova in the quarterfinals of the German Open.
Pegula, who beat the fourth-seeded Karolína Plísková for the fourth time this year on Thursday, was unable to follow up against the seventh-seeded Azarenka, losing 6-2, 5-7, 6-4.
The Belarusian was playing her first grass-court quarterfinal since Wimbledon in 2015.
The 106th-ranked Samsonova needed almost 2 1/2 hours to shock Keys 7-6 (4), 2-6, 7-6 (0).
Samsonova plays Azarenka in her second career semifinal on Saturday.
Alizé Cornet and Belinda Bencic will meet in the other after coming through third-set tiebreaks in their quarterfinals.
Cornet saved a match point before upsetting the sixth-seeded Garbiñe Muguruza 4-6, 6-3, 7-6 (5), and the fifth-seeded Bencic overcame Ekaterina Alexandrova 6-4, 4-6, 7-6 (4).
It will be the 31-year-old Cornet's first semifinal on grass.
Bencic is through to her fifth on grass.
The Swiss hit nine aces against Alexandrova, who replied with 15 of her own.
Bencic won the first two points in the tiebreak and held on to her lead.