Watch Robin Williams' heartfelt Oscars speech for 'Good Will Hunting'

Robin Williams won one Oscar during his career, for best supporting actor in 1998 for his role in Good Will Hunting.

The actor, who died Monday at 63, bested Anthony Hopkins, Greg Kinnear, Burt Reynolds and Robert Forster to win the statuette, and his acceptance speech has all of the sincerity and silliness you'd expect from Williams.

MORE: Good Will Hunting bench turned into Robin Williams memorial

He thanks young Matt Damon and Ben Affleck ("I still want to see some IDs"), who also won that year for the movie's screenplay, his then-wife Marsha Garces, to whom he was married from 1989 to 2008, and his father, "up there," he says, gesturing above.

APPRECIATION: Robin Williams' comic genius

GALLERY: Robin Williams: 1951-2014