Los Angeles, Feb 27: Actor Casey Affleck won an Oscar in the Best Actor category for his role as a grieving brother in film "Manchester by the Sea" at the 89th Annual Academy Awards.He was announced as the winner of the golden statuette at the ceremony -- being held at the Dolby Theater in Hollywood on Sunday night.Casey appeared to be surprised when his name was announced and as his brother and actor Ben Affleck excitedly lunged towards him to kiss him. Other nominees were: Andrew Garfield (Hacksaw Ridge), Ryan Gosling (La La Land), Viggo Mortensen (Captain Fantastic) and Denzel Washington (Fences).The first word as Casey walked upto the stage to accept the award was "Dammit"."It means so much to me. Thank you everyone", he said.He also thanked Washington and said: "One of the first people who taught me how to act was Denzel Washington, and I just met him tonight."It is his first Oscar, and Casey was was nominated once before, in 2008 Best Supporting Actor for "The Assassination of Jesse James by the Coward Robert Ford".In "Manchester by the Sea", Casey character is seen as guardian of his teenage nephew, Patrick after his brother's sudden death. And then narrates how he comes out his self-imposed sentence of solitary confinement and also throws light on his struggles to stick around a world without his brother and this new responsibility.Casey said he is "really proud to be a part of this community"."I'm just dumbfounded that I'm included", he added.Concluding his acceptance speech, Casey said: "I wish I had something bigger and more meaningful to say." And then thanked his family and love of his life for the constant support. He was presented the award by last year's best actress winner Brie Larson.