Alcaraz caps 'difficult week' with first Monte Carlo Masters title
The 21-year-old Spaniard, already a four-time Grand Slam winner, dropped the opening set but came back hard to take the next two at the cost of a single game as he cleaned up 3-6, 6-1, 6-0, albeit helped by a limping Musetti.
It marks a sixth Masters title for Alcaraz and is his most prestigious title since winning Wimbledon last year.
It was also his first win on clay since winning the French Open last season, although in mitigation he only had one tournament after that when he missed out on gold at the Paris Olympics.