Sania Mirza and Bethanie Mattek-Sands defeated Liezel Huber and Janette Husarova to enter the women's doubles semifinal at the Porsche Tennis Grand Prix here.
The Indo-American pair got past the American-Slovak combination 7-5, 6-4 in the quarterfinals played on Friday.
Sania-Bethanie next play Germany's Angelique Kerber and Andrea Petkovic on Saturday night.
Bethanie is also enjoying a great run in the singles event where she faces Li Na of China in the semifinals. The American defeated local hope Sabine Lisicki 6-4, 6-2 in the quarterfinals.
"I played Sabine last year at the French Open and she's been playing well again this year," Mattek-Sands was quoted as saying by WTA website. "She's had some good results and has a lot of confidence. I knew I had to play well.
"I had some good support out there from the crowd, even though I was playing a German girl - and I'm looking forward to the same tomorrow. To be in the semis after coming back from match point down in the qualifying is a pretty good feeling, and obviously beating Sara yesterday was a great win for me.
"This has definitely been one of the best weeks of my career."