Thiem reached his first grand slam final at Roland Garros with a comfortable defeat of Marco Cecchinato, meaning he will face Nadal after the 10-time victor swept aside Juan Martin del Potro in the second semi-final.
Once Nadal stole the opener with a break in the 10th game, it was one-way traffic as he left Del Potro trailing in a cloud of Parisian clay dust to set up a final against Dominic Thiem.
Del Potro, 29, is a popular figure among tennis fans, with affection for him growing further as a result of the catalogue of injuries he has suffered in recent years.
"It's a challenge that every player wants to have", he said. The vanquished del Potro acknowledged as much as he reflected on the brief stretch where he was able to put up some resistance to Nadal's unremitting intensity.
"Today in the first set, for example, I was not playing great, was suffering because he was playing better than me".
In Madrid, Thiem said the key was to be positive against Nadal.
The big serves, the monstrous forehands and the clever changes in pace seemed to have an effect on Nadal in the first set.
Croatian Cilic played an terrible game when serving for the set, making four unforced errors, but he was gifted another chance to serve for the set after breaking Del Potro again and levelled the match at the second time of asking.
Halep will face Stephens after the US Open victor maintained her ideal record against fellow American Madison Keys with a 6-4 6-4 win in the other semi-final.
But Nadal's domination on the Roland Garros clay, where his record now stands at 85-2, is without equal and he will be a huge favourite to beat Grand Slam final debutant Thiem.
World number 72 Cecchinato stunned Roland Garros on Tuesday by following up his surprise wins over top-10 seeds David Goffin and Pablo Carreno Busta with a breathtaking victory against 12-time major champion Djokovic.
"I couldn't play my best because of him", said del Potro, the 2009 U.S. Open champion.
Nadal will face either Croatian third seed Marin Cilic or Juan Martin del Potro, the fifth seeded Argentine, in the semifinals. I think this is too good of an opportunity for Thiem to pass up. "But I think he's very enthusiastic".
After struggling in his quarterfinal against Diego Schwartzman, Nadal is approaching his best form ahead of the final and hopes are high that the Spanish star will emerge victorious.
"I believe that there is chances, limited chances in your career", Nadal said.
Dominic Thiem insists he has a plan to beat Rafa Nadal after reaching the first Grand Slam final of his career. Cecchinato made some headway by repeatedly using drop shots, but Thiem eventually started tracking them down well.
Conditions will play a huge rule in Thiem's chances.
Del Potro found the breakthrough at 5-5 in a tight fourth set, when Cilic sent a backhand long to give him a break and he went on to serve out the match.