World number five Caroline Wozniacki overcame Simona Halep to reach the Stuttgart Grand Prix final.
In a nearly three-hour contest, Wozniacki came through 7-5 5-7 6-2 against the Romanian second seed.
The Dane, 24, is looking for her second title of the season, after her win at the Malaysian Open in March.
She will meet Angelique Kerber in Sunday's final after the German eased to a 6-3 6-1 win over American Madison Brengle.
Kerber needed only 58 minutes to claim her 10th win in a row to beat Brengle, who had knocked out Wimbledon champion Petra Kvitova in the second round.
Kerber is bidding for a second straight title, and the fifth of her career, having won in Charleston two weeks ago.