Danish teenager Holger Rune continued his remarkable run on clay in Munich by beating Oscar Otte in straight sets on Saturday to reach his first final on the ATP Tour.
Rune, who turned 19 on Friday, had stunned top seed and Olympic champion Alexander Zverev in the second round on Wednesday in the Bavarian capital.
Rune produced another mature display to seal a 6-4, 6-4 win over Otte to set up a title decider with Dutchman Botic van de Zandschulp, also through to his maiden ATP final.
Van de Zandschulp, 26, needed nearly three hours to muscle past Serbia's Miomir Kecmanovic.
He held his nerve to claim a 2-6, 7-6 (7/4), 6-4 victory and build on Friday's quarter-final upset of second seed Casper Ruud.