Teenager Jakub Mensik beat Gael Monfils to become the youngest player to reach the final of the Qatar Open.
Mensik, 18, gained a key break at 4-3 in the third set before going on to hold serve as he won 6-4 1-6 6-3 in Doha.
“I am speechless,” he said. “It is amazing. Hopefully not the last one [final].”
The Czech, who beat Briton Andy Murray earlier in the week, will face Russian Karen Khachanov in Saturday’s final.
Mensik added: “I have to say this performance was one of the best in my entire life.
“I am so glad I reached this level in the semis, so hopefully tomorrow I play like this. An amazing feeling with my first ATP final.”
Khachanov came through his last-four test against Australia’s Alexei Popyrin 7-6 (14-12) 6-2 and is looking to win a sixth tour-level title.