Nadal, 30, has now won 10 consecutive matches and is aiming for his 10th French Open title next month.
Nadal had to save a break point in the opening game of the match but was able to quell Thiem's bright start.
"I got three matches in three days against all different players", Murray said.
A solitary break in the second set proved enough for Nadal to reach his fifth final in 2017 and he will today aim to win his 51st title on clay.
Andy Murray expressed his satisfaction at reaching the last four of the Barcelona Open for the first time after gaining a measure of revenge over Albert Ramos-Vinolas.
A win for the world number five would make it his second title of 2017 and his 10th overall Barcelona title. With the win in Barcelona, he's collected 500 more ATP points and is now within 300 points of leader Federer in the ATP Race to London at the ATP Finals tournament at the end of the year.
The Frenchman will take on Aljaz Bedene in Sunday's final after the British number four defeated Serbian Laslo Djere 6-2 6-4. It also makes him the only player to win two singles titles ten times each.
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Précisant que 'l'enquête en est à ses débuts', le NHS avait néanmoins identifié le virus concerné comme étant Wanna Decryptor. Si au bout de trois jours, il n'y a pas de paiement, le prix double.
Budapest victor Lucas Pouille of France moves into a career-best 14th position as 20-year-old Russian Karen Khachanov soars 14 places to 42nd after reaching the Barcelona quarterfinals.
Nadal has won so many titles in Barcelona, that the tournament even named its center court after him in time for the Spaniard to win the trophy on his own court, Pista Rafa Nadal.
Briton Murray was overpowered by Ramos-Vinolas in the first set and had to save three break points in the ninth game of the second before tying the match.
WTA PORSCHE GRAND PRIX: Maria Sharapova's first tournament since her controversial return to tennis ended Saturday after losing to Kristina Mladenovic of France in the Porsche Grand Prix semifinals in Stuttgart, Germany.
Bedene said: " I was working really hard in the pre-season and staying solid, so I am really happy with how I am playing.
Nadal said of Chung: "He has good potential, great backhand and very quick".
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