Rio de Janeiro - Dominic Thiem and Pablo Carreno Busta will face off in the final of the clay-court at the Rio Open.
Thiem defeated Albert Ramos-Vinolas 6-1, 6-4 on Saturday to advance, and Carreno Busta ruined the night of 18-year-old Norwegian Casper Ruud, 2-6, 7-5, 6-0.
Ruud was trying to become the youngest to reach an ATP singles final since Kei Nishikori nine years ago.
Entered as a wild card, Ruud had a match point leading 5-4 in the second set. But when he failed to convert, it all slipped away.
"I didn't play too well in the last set," said Ruud, whose father Christian was a former top-50 player.
"I had my chances, obviously. I was one point away. Toward the end of the second and the third I just got into this rhythm I couldn't get out of."
Thiem, 23, will be seeking an eighth ATP singles title, five of which have come on his favoured clay surface.
"Now I'm feeling really good again about my game," Thiem said after playing hard-court events.
"On clay, I almost all the time feel great. I knew that this week was going to be very important because I didn't have much confidence before."
Thiem broke Ramos-Vinolas three straight times to take the first set, and one more time to start the second.
The second-seeded Thiem instantly became the favourite when top-seeded Nishikori was beaten in the first round by Brazil's Thomaz Bellucci.
Thiem has not lost a set in four matches in Rio.
Meanwhile, Carreno Busta is after his third ATP singles title.
He is also in the doubles final afterward with partner Pablo Cuevas of Uruguay. He's likely to get about a one-hour break, or less.
"To get to the singles final in a tournament like this is really tough, even more so to also do it in doubles. It's been a great week so far," the Spaniard said.
Collated results from the ATP Rio de Janeiro Open on Saturday (x denotes seeding):
Dominic Thiem (AUT x2) bt Albert Ramos (ESP x5) 6-1, 6-4
Pablo Carreo-Busta (ESP x4) bt Casper Ruud (NOR) 2-6, 7-5, 6-0