Musetti, who says he has put some order in his mind and game in what has been something of a renaissance this spring, did not let frustration take the best of him after losing the second set and once he found his groove, there was no stopping him. 15th seed Tiafoe gradually lost the plot, twice arguing with the chair umpire over line calls.
He bowed out with yet another routine shot into the net, his 'Big Foe' neck chain dripping with sweat as a testimony of the battle just fought.
"Definitely Frances did not start the way he wanted but today was really complicated, it was so windy and difficult to mange to properly hit the ball," said Musetti, the only man to reach at least the semi-finals of every main claycourt event this season.
"The third set was a fight and even if I was a little tired I found the extra energy to win this set and the last set was probably the best set of this match."
Musetti is one of the rare top players using the single-handed backhand, a vintage shot often praised by tennis connoisseurs.
"We are Italian, we are elegant," he joked. "Joke aside, I have a little bit of a retro style."
With the main arena almost full, Musetti got off to a strong start, with his heavy top spin proving tough to handle for Tiafoe, who dropped serve in the second game.
The Italian, however, was not completely flawless and he faced a break point at 4-2, which he saw off thanks to his mesmerizing backhand.
He sealed the opening set on his opponent's serve when Tiafoe's volley sailed wide.
Musetti's game, however, needed some fine-tuning and Tiafoe jumped on the occasion to bank on errors here and there to snatch an early break in the second set.
He held serve throughout to level the contest as Musetti seemed to struggle adjusting to the windy conditions on Court Philippe Chatrier.
Musetti dug deep in the third and played a near-perfect game on Tiafoe's serve to surge 2-1 ahead. A modest second serve met Musetti's powerful cross-court return and after trading heavy top-spin shots, Tiafoe attempted a crafty drop shot, but the Italian charged forward for a clinical backhand winner on the baseline.
The fourth set looked more like a post-match cool-down for Musetti, who would not be distracted by Tiafoe's antics.
