Alcaraz made a wayward start against Musetti, seeing an early break lead cancelled out before his 23-year-old opponent reeled off four games in a row.
Musetti’s accuracy won out over his opponent’s pacy hitting, with the Italian clinching the set on an outrageous drop-shot winner from behind the baseline.
Alcaraz hit 14 unforced errors in the first set, 11 off the forehand alone, but settled quickly into the second.
A roar of “vamos” greeted a missed Musetti forehand that handed Alcaraz the break lead, with the Spaniard moving around the court with more conviction and asking the crowd for appreciation after hitting a superb backhand winner.
He won five games in a row but Musetti had a glimmer of a chance. He created five break-back points as Alcaraz served for the set, but the second seed saved them all, ultimately closing out an eight-minute game to force a deciding third set.
That was barely competitive, though, as Musetti was hindered by a right thigh injury, needing treatment after going 3-0 down, and could barely move.
Alcaraz promptly whizzed through the set, raising his arms in celebration before consoling Musetti.
The victory also means Alcaraz will replace Germany’s Alexander Zverev as world number two when the rankings are updated on Monday.
Later, British pair Julian Cash and Lloyd Glasspool were beaten 1-6 7-6 (10-8) 10-8 in the men’s doubles final by home favourite Romain Arneodo and France’s Manuel Guinard.
