Casey Affleck insists he had no reason to thank his brother Ben at the Golden Globe Awards.

Casey Affleck

Casey Affleck

The 'Manchester by the Sea' star can't understand why his older sibling said he was "taken aback" at not being mentioned when Casey picked up the Best Actor prize earlier this month.

While the 41-year-old actor admits he has "a lot" to thank his 44-year-old brother for, he doesn't think on stage accepting a prize for a movie his brother had no involvement with was the right time to do it.

Speaking on E's 'Live From The Red Carpet' at the Screen Actors Guild Awards on Sunday (29.01.17), he said: "I was sort of just curious as to what I was supposed to be thanking him for.

"Maybe he thought he was involved in the movie, but he wasn't. There's a lot of things to thank Ben for, but standing at the Golden Globes was not the moment to do it since he wasn't involved in the movie."

At the SAGs, Casey was nominated for Outstanding Performance by a Male Actor in a Leading Role - an accolade eventual winner Denzel Washington even expected him to win - but insisted he hadn't prepared a speech for the occasion.

He said: "I just try to thank as many people as I can because it seems appropriate and conventional and the right thing to do because there's so many people involved in a movie, until they play the music and someone kicks me off-stage."

While Casey always thought the movie - in which he plays a loner janitor who is forced to confront the horrors of his past - was going to be "special", he admits it was a challenge to get the tone right.

He said: "When I first read the script, I knew it was a very special script, and then, once they asked me to be involved, I wasn't sure it would turn out to be a very special film.

"Over the course of shooting the movie, you never know if something's going to be good or not.

"I think the hardest part was really just trying to do service to the script because it was so layered and so complex and so perfectly written that you just felt like, if you cannot mess it up, you'll be serving the movie in the right way. It was a very heavy move and also a very funny movie and you want to be able to pull both off."

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