The astounding 'King of Clay' earned a record-breaking 12th French Open title by overpowering the gutsy Thiem 6-3 5-7 6-1 6-1.
No other player, male or female, has won a single grand slam as many times.
Thiem and Nadal's long-time rival Roger Federer, who the defending champion beat comprehensively in the semi-finals, were under no illusions about the enormity of the task beating the world No.2 on the red dirt represents when speaking to the media this week.
World No.4 Thiem was not up to it when the pair met in last year's final. He was unable to cope with the Spaniard's unforgiving shot making and found himself clinically swept aside in straight sets.
It looked like it could be a different story this time around, but, as he always does, Nadal simply reached a level no other player can match and secured a return to his Roland Garros throne.
Thiem darted around the court at magnificent pace in the first set, returning shots the No.2 seed would normally be turning for his towel after hitting.
His approach made Nadal sweat. The Austrian mixed some of the fiercest groundstrokes with the deftest of drop shots to keep his opponent on his toes.
The pair was consistently embroiled in brutal, punishing rallies. The crowd was on the edge of its seats. Spectators were gasping in awe as seemingly impossible shots crossed back and forth over the net. They shushed one another mid-point, hoping they may help prolong the battle between two masters of the clay. It was enthralling and tiring to watch.
Not many gave Thiem much of a chance, particularly after he had to go through five sets to get through world No.1 Novak Djokovic in a match that was interrupted three times because of rain and did not finish until Sunday (AEST), less than 24 hours before the scheduled start time of the final.
It was the fourth day in succession that he had taken to the court, while Nadal entered the final having played just twice this week.
However, it was Thiem who struck the first blow. A blistering forehand into the corner set up break point and although Nadal was able to loop the next one back, the No.4 seed smashed it right past him.
That is not enough against the world number two, though. His pinpoint forehand got the contest back on serve and he charged from well behind the baseline to chase down one of the 25-year-old 's exquisite drop shots and reply with his own for break point. When Thiem failed to stave it off, the first set was effectively sealed.
A score of 6-3 scarcely seemed fair. Thiem must have been wondering at the changeover what more he could have done; in the 95 matches Nadal has played at Roland Garros it will be a question that has been asked by his opponents time and time again, with Robin Soderling and Djokovic handing him his only losses in Paris in 2009 and 2015 respectively.
Unsurprisingly, the intensity dipped in the second set. Thiem performed well behind his own serve but claimed just one point on his opponent's, before the 33-year-old crumbled in the final game and four straight errors put the match back on level terms.
Seemingly annoyed at dropping just his second set of the tournament, Nadal came out with a renewed energy in the third and the man on the other side of the net did not have the reserves to match him. After hitting an incredible forehand pass for his second break, Nadal erupted. An immense roar. A pumping fist. A decisive moment.
Another gear had been found and there was no let up from the relentless Spaniard, leaving an exasperated Thiem with his arms outstretched after a rip-roaring forehand denied him a break.
The unyielding left hander was suddenly too much for Thiem to handle. The match was taken out of his hands, and into Nadal's, yet again, went La Coupe des Mousquetaires.