The 28-year-old Petrucci could clearly be seen crying after he crossed the line at the Mugello circuit for his first win on his 125th start in the premier class. Petrucci's Ducati teammate Andrea Dovizioso was third, 0.338 off the pace.
Marquez, who had won three of the previous four races on his Honda, extended his lead in the standings to 12 points over Dovizioso. There was disappointment for seven-time champion Valentino Rossi, who crashed out early in his home race.
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