Rain had blighted several days of the tournament to this point, but Sunday saw no showers as Nadal breezed to a victory in straight sets by a score of 6-4, 6-3, 6-2.
Nadal's triumph marks the sixth consecutive Grand Slam won by either him or 20-times major champion Roger Federer.
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Nadal entered Sunday's final 85-2 lifetime at Roland Garros, and that fact alone put Thiem in a precarious position before the proceedings even got underway.
Sunday marked the first time Nadal had faced a player from a younger tennis generation in a Grand Slam final. Since then, the Spaniard has been imperious.
Rafael Nadal briefly interrupted the French Open final against Dominic Thiem in the third set with an apparent problem with his left wrist. At the following changeover, Nadal was given a salt pill by a doctor and had his left forearm massaged by a trainer.
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Nadal, however, turned the screw in the 10th game and Thiem seemed to grow nervous, sending a forehand long to hand his opponent the opening set. That led to 34 winners (eight more than Nadal), but also 42 unforced errors (18 more than Nadal). 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.
The duo have met nine times throughout their career, all on clay, with Nadal taking six meetings to Thiem's three. After guzzling water during his visit from the doctor, Nadal was back to playing his unmistakable brand of almost unbeatable clay-court tennis. The world No. 8, too, was the last man to overcome Nadal on clay, last month in Madrid.
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