Dominic Thiem has now beaten Rafael Nadal on clay in four straight season.
BARCELONA, Spain (AP) Dominic Thiem defeated Rafael Nadal 6-4, 6-4 in the Barcelona Open semifinals on Saturday, becoming the first player other than Novak Djokovic to defeat the Spaniard on clay four times.
Thiem will try to win his second title of the year on Sunday in a final against Russian Daniil Medvedev, who upset fourth-seeded Kei Nishikori 6-4, 3-6, 7-5.
The fifth-ranked Thiem won his first title of the season by defeating Roger Federer in the Indian Wells final in March. It will be his first final on clay since last year's French Open, where he lost to Nadal.
It was the second straight semifinal loss for the second-ranked Spaniard, who was coming off a defeat to Fabio Fognini in Monte Carlo.
Nadal was seeking a record 12th Barcelona title, and fourth consecutive.
Thiem lost the Barcelona final to Nadal two years ago, but the Austrian has beaten the 17-time Grand Slam champion on clay in each of the last three seasons.
Only two other players have beaten Nadal on clay three times - Fognini and Gaston Gaudio.
Thiem has yet to lose a set this week, and he was in control early on against Nadal, putting pressure on the Spaniard's serve from the start. He broke Nadal in the fifth game of the first set and had four break opportunities immediately after that before Nadal recovered to hold.
The one break ended up being enough for Thiem in the first set, and he moved ahead of the Spaniard again at 2-2 in the second set. He was down 0-40 while serving for the match, but came back to close out the victory at the Rafa Nadal main court.
Nishikori, the winner in Barcelona in 2014 and 2015, was broken twice in the final set against Medvedev, including in the final game of the match.
It was a tour-best 25th win this year for the 14th-ranked Medvedev, who was coming off a semifinal appearance in Monte Carlo. It will be his first-ever clay court final.
''I'm really happy that I managed to hold my nerves, to try to come back, and I managed to come back,'' Medvedev said. ''I'm just happy to be in the final.'