Jimmy Fallon is apologizing after a clip from a 20-year-old “Saturday Night Live” sketch resurfaced that featured the future “Tonight Show” host in blackface.

In the vintage “SNL” sketch, Darrell Hammond is impersonating Regis Philbin, who welcomes guest Chris Rock — who’s played by Fallon with his skin darkened.

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Backlash quickly ensued after a Twitter user posted the video, along with the hashtag #jimmyfallonisoverparty.

Fallon took to social media to do some damage control and issued a full apology.

“In 2000, while on ‘SNL’, I made a terrible decision to do an impersonation of Chris Rock while in blackface. There is no excuse for this,” he wrote.

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“I am very sorry for making this unquestionably offensive decision,” he added, “and thank all of you for holding me accountable.”

Jamie Foxx commented on an E! News Instagram post about the story. Foxx defended Fallon and called the blackface allegations “a stretch.”

“He was doing an impression of Chris Rock. It wasn’t blackface,” Foxx wrote. “We comedians I know it’s a tough time right now. But this one is a stretch. On a show called “In Living Color” we played every race. Let this one go. We got bigger fish to fry.”

ET Canada has reached out to an “SNL” spokesperson for comment.

Check out some of the Twitter backlash to Fallon’s blackface sketch:

Meanwhile, in January 2017 Fallon did his Chris Rock impression – with the voice, no blackface – when he hosted the Golden Globe Awards.