Mark Ruffalo Says There Should Be 'No Shame' Around Mental Illness as He Accepts 2021 SAG Award

Mark Ruffalo has officially nabbed his third Screen Actors Guild Award!

On Sunday, the actor, 53, won the award for outstanding performance by a male actor in a miniseries or television movie for his dual role in the HBO miniseries I Know This Much Is True. Ruffalo previously received SAG Awards for his roles in Spotlight in 2016 and The Normal Heart in 2015.

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He beat out fellow nominees Hugh Grant (The Undoing), Ethan Hawke (The Good Lord Bird), Bill Camp (The Queen's Gambit) and Daveed Diggs (Hamilton).

Ruffalo called receiving the award a "crown achievement" of his career.

"Acting doesn't happen in a vacuum. It happens between people in a magical place, created by a director like Derek Cianfrance and a writer like Wally Lamb," he said while accepting the honor. "Mental illness is a real thing, and I just think it's really important that we're honest and open about it and have no fear and no shame. So, thank you so much."

In I Know This Much Is True, Ruffalo played twins Dominick and Thomas Birdsey, the latter of whom is schizophrenic and in an asylum that Dominick tries to get him out of over the course of the series.

In addition to playing two characters, Ruffalo also underwent a physical transformation, losing 20 lbs. to play Dominick — only to gain 30 lbs. weeks later to play Thomas.

"We didn't want it to be like I run and throw a wig on and do the same scene in the same day," Ruffalo said at the TV Critics Association Winter Press Tour last year. "So we took six weeks off to really separate these two guys."

The 27th annual Screen Actors Guild Awards are airing from 6-7 p.m. PT/9-10 p.m. ET on TNT and TBS.