Andrea Petkovic upset top-seeded Jelena Jankovic 6-4, 6-3 Friday in the inaugural Nurnberger Versicherungscup.
Petkovic will play either Simona Halep or Lucie Safarova in the final on Saturday.
Petkovic reached her first WTA final since October 2011. The former top-10 player missed several months with various injuries and dropped to 103rd in the world.
Petkovic dropped her serve early in the match but recovered to take the first set.
Serving for the match, Petkovic trailed 0-40. But Jankovic had several errors and ended the match with a backhand that sailed wide.