It's a good thing Zach Galifianakis introduced himself on camera at the start of the Screen Actors Guild Awards on Sunday (Jan. 25) -- otherwise, you probably wouldn't have recognized him!

The comedic actor first shocked fans with his dramatic weight loss at the New York City premiere of 'Birdman' last October, but he showed he's keeping the pounds off on the biggest stage yet, appearing at the awards show televised live from Los Angeles.

The 45-year-old helped kick off the event by looking at the camera and seriously intoning, "I'm Zach Galifianakis." He then looked to the side and asked comically, "I'm an actor?"

Many home viewers probably dropped the popcorn at that point. The famously plump and heavily bearded 'Hangover' star was nearly unrecognizable with his new slimmed-down, relatively clean-shaven look. He even sported a Jared Leto-like man bun!

The 'Between Two Ferns' host has credited quitting drinking with his thinner physique. "I was having a lot of vodka with sausage, delicious but bad for you," he told late-night host Conan O'Brien in May 2013.

Galifianakis was at the SAG Awards alongside his 'Birdman' castmates, including Michael Keaton, Emma Stone and Edward Norton. They took the award for Outstanding Performance by a Cast in a Motion Picture. Their winning moment instantly went viral when Naomi Watts tripped on Emma's gown and nearly fell down. Emma's face was PRICELESS. (Watch it all go down here.)

A noticeably heavier Zach Galifianakis attends the U.K. premiere of 'The Hangover Part III' in May 2013.

Neil P. Mockford, Getty Images

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