The 'Holdovers' actor also thanked his later father Bart Giamatti in his acceptance speech, saying of the award, "This would make him really happy"
The Holdovers star beat out fellow leading men Bradley Cooper for Maestro, Leonardo DiCaprio for Killers of the Flower Moon, Colman Domingo for Rustin, Cillian Murphy for Oppenheimer and Jeffrey Wright for American Fiction.
Giamatti, 56, began his acceptance speech with a hilarious nod to his post-Golden Globes In-N-Out moment, joking to laughter from the crowd, "Wow, guys. I didn't think my week could get any better than going viral for eating a cheeseburger."
"Seriously guys, I need that endorsement, so let's all just pray for me," he quipped.
Aside from cast, crew, his team and the studio, Giamatti thanked his son Samuel, girlfriend Clara Wong and his late father Bart Giamatti, "who never saw me act professionally" before his death.
"He was a literary critic, and so you couldn't get away with anything but good work with him," the actor went on. "This would make him really happy, and that makes me really happy. So thank you."
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It’s the veteran actor’s sixth overall nod, including wins for Sideways and 2006’s Cinderella Man.
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