But this will be the first time they've met in a Grand Slam final.
Thiem broke back immediately as he continued to go for his shots, and he saw off a break point to hold for 2-2.
'Let me enjoy this title, ' he said after the 6-4 6-3 6-2 win.
Rafael Nadal's stranglehold on the French Open has endured so long and remains so strong that he has even out-lasted his favorite Court Philippe Chatrier stadium and will probably still be winning the title when it gets a roof in 2020. Like so numerous pretenders, Thiem just did not have quite the same level of consistency to derail the Spaniard, who ruthlessly targeted his flowing backhand. I can't see past another Nadal victory but believe Thiem will take a set off the great man.
Nadal now stands at 86-2 at French Open and continues to remain unbeaten in finals in Paris.
Nadal threw his arms skywards and turned to his entourage including coach and fellow Mallorcan Carlos Moya and his uncle Toni, who stood down from his coaching role a year ago after his nephew worn his 10th French crown.
"Along with Nadal, he is literally still the world of men's tennis, and to not play a Grand Slam on a surface that we play for two months, on which everybody has grown up on, to not come to the showpiece of claycourt tennis, it hurts the tournament, it hurts professional tennis, it hurts men's tennis". I am happy that other people have things, and I am very satisfied, and I feel very lucky with all the things that happened it me.
As if the task was not daunting enough for Thiem, the early signs were even more ominous.
That it was not was testimony to Nadal's level, which never wavered, despite everything Thiem threw at him.
In the tie-break of the tournament, Djokovic trailed 3-0, then played a couple of stunning points to save match point and give himself a couple of set points, before losing 13-11.
Thiem says he is "confident" his first appearance in a Grand Slam final will not be his last.
Ramos is now in Russian Federation with the Spanish squad as they prepare for the World Cup, but took time out to tweet in Spanish, hailing Nadal for his "dynasty on clay", calling him a "tennis legend" and "sporting hero". At one point finally, Thiem tried going around the post in the penultimate game, just after a Nadal cross-court backhand return seared so close over the net cord that it made the Parisians murmur.
He bagged the second set when Thiem sent a backhand long.