Fifth-seeded Hubert Hurkacz defeated Olympic champion and home favourite Alexander Zverev to reach the final at the Wimbledon tune-up grass-court tournament in Halle, Germany.
Hurkacz, who won the Halle title in 2022, overcame Zverev 7-6 (7-2), 6-4 in 1 hour 33 minutes on Saturday.
In Sunday's final, he will face either world number one Jannik Sinner or China's Zhang Zhizhen.
The Pole produced an impressive serving display in the semi-final, firing 17 aces and saving all four break points he faced to earn his fifth top 10 grass-court win.
Germany’s Zverev was seeking his first trophy in Halle, after having advanced to the title match on home soil in 2016 and 2017.
Halle is among the big warm-up tournaments for Wimbledon which starts on July 1.