The clay-court tournament is a tuneup for the French Open.
Cilic served up six aces and breezed past Tommy Haas of Germany 6-3, 6-4. Kohlschreiber outlasted second-seeded Feliciano Lopez of Spain 6-2, 6-7 (4-7), 6-4 despite converting only three of 13 break-point opportunities.
Cilic, who hails from Croatia, will bring a 6-6 career record in finals up against Kohlschreiber, who is 3-2 in championships.
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