Alexander Bublik eased past home hope Alexander Zverev 6-3, 7-5 to reach the final of the Halle ATP tournament on Saturday.
Bublik, 26, will play his first final of the season in the Wimbledon warm-up grass-court event against either Spaniard Roberto Bautista Agut or Russian Andrey Rublev.
Kazak Bublic won his only title last year in Montpellier against Zverev and now holds a 3-1 record against the German.
On Saturday, Bublik took less than an hour and a half to dispatch the former world number two, firing down 14 aces with a strong service game.
In the first set, he quickly took the lead with a break in the fourth game (3-1), and then counted on his serve (6-4) to pull him through.
The two players duelled until 5-5 in the second set, when Zverev collapsed, allowing Bublik to confidently seal victory 7-5.