Defending champion Angelique Kerber reached her second successive Porsche Grand Prix final with a 6-4, 4-6, 6-2 defeat of Petra Kvitova.
Kerber, the No. 2 seed, saved 10 of the 13 break points she faced Saturday and converted five of her 10 opportunities to beat the fifth-seeded Czech in 2 hours and 4 minutes on her first match point.
The top-seed, Agnieszka Radwanska, was to play qualifier Laura Siegemund in the other semifinal at the indoor clay-court tournament later Saturday.
Siegemund will be playing in her first semifinal, bidding to make it an all-German final in her hometown on Sunday.