Hamburg - Home favourite Tommy Haas will face Juan Monaco in Sunday's final of the Hamburg clay-court event after ousting Croatian fourth seed Marin Cilic 7-6 (9/7), 6-0 in Saturday's semi-final.
Wildcard Haas, the world No 49, remains on course to become the first German winner of the event since Michael Stich in 1993.
Earlier, Argentine third seed Monaco got the better of top seed Nicolas Almagro of Spain 3-6, 6-3, 6-4 in the first semi-final.
The Argentine will be appearing in his second consecutive final, having lost to Serbia's Janko Tipsarevic in the Stuttgart decider last weekend.
Monaco took a little over two hours to record his third victory in seven encounters with Almagro, who is ranked 10th in the world.
The 28-year-old from Buenos Aires is bidding for his third title of 2012, after previous successes at Vina del Mar in Chile and Houston, Texas.