It was an emotional victory for the 24-year-old Italian, who won the Moto2 title back in 2020, as it was just over a year on from the tragic passing of team boss Fausto Gresini.
“My feeling now is incredible because I pushed from the start but the most important was to save the tyre until the end of the race,” he said.
“In the end, Pol was really close to me and then I thought I could try to win the race...then I overtook him on the first corner when he went wide.
“I want to dedicate this victory to Fausto because he has pushed me a lot from the sky, it’s fantastic for all the team, I think we have cried, all the guys...I want to say thanks to everybody for this.”
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Brad Binder finished second at the flag then Aleix Espargaro was third.
In the Moto3 class, it was Italian Andrea Migno on the Rivacold Snipers Honda who claimed the first podium of 2022.
There was another Italian winner in Moto2 when Celestino Vietti claimed victory for Mooney VR46 Racing Team, converting pole into victory.