McGregor, 46, took home the statue for best performance by an actor in a limited series or motion picture for television during Sunday night’s award show for his role in Fargo.
McGregor thanked his costar and girlfriend, Mary Elizabeth Winstead, saying, “I’ve always loved being an actor and hanging out with actors and I got amazing actors to work with on this and it wouldn’t be any Emmett or Stassi without David, Michael, Carrie Coon and there would be no Rey without Mary Elizabeth Winstead so thank you very much.”
Winstead, 32, and McGregor were spotted in October sharing a kiss. Following the sighting, a family source confirmed to PEOPLE that McGregor and Eve Mavrakis, his wife of 22 years, have been separated since May 2017.
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The actor pointedly thanked his ex during his acceptance speech, saying, “I want to take a moment to thank Ev, who always stood beside me for 22 years and my four children, I love you.”
Mavrakis and McGregor share four children together: Clara, 21, Esther, 16, Anouk, 7, and Jamyan, 7.
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This is McGregor’s fourth Golden Globe nomination and first win. He was previously nominated in 2013 for Salmon Fishing in the Yemen, and twice in 2002 for Moulin Rouge in categories of best actor in a musical or comedy and for best original song, “Come What May.”
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In an interview with the Hollywood Foreign Press Association, McGregor said the challenge of filming Fargo was learning the dialogue of two characters.
“I had two roles to learn and I hadn’t thought of that before I started,” he said. “All I was doing was learning lines, I was on set acting as Emmett, I was on set acting as Ray, or I was in the makeup chair or I was learning lines.”
The 75th annual Golden Globes were presented live on NBC from the Beverly Hilton in Beverly Hills, California, on Sunday.