A video from the 1990s of noted Hollywood actor Will Smith joking about a man's baldness resurfaced online just hours after his infamous Oscars slap.

The footage of Smith comes from "The Arsenio Hall Show" in 1991, where the "Fresh Prince of Bel Air" star mocked John B Williams, the bassist for the show's house band.

"He's got to wax his head every morning", Smith said, pointing to Williams in the old clip.

Some members of the audience could be heard laughing and clapping, while others were heard booing at the joke, which prompted Smith to shoot back.

"It's a joke. Come on," he said.

Smith's words from the old clip bear a startling resemblance to comedian and actor Chris Rock's defence of his ill-fated version of the joke at the 94th Academy Awards.

Smith smacked Rock in the face and shouted a vulgarity at the comedian in a shocking moment, overshadowing the Oscars ceremony earlier this week.

The incident began when Rock was roasting some of the nominees and made fun of Smith's wife, Jada Pinkett Smith.

"Jada, I love you. 'G.I. Jane II,' can't wait to see it," he said, referencing the 1997 film "G.I. Jane" in which actress Demi Moore shaved her head.

It was unclear whether Rock was aware that Smith's wife suffers from the autoimmune disorder alopecia, which causes hair loss and balding.

But Smith quickly stood up and marched toward the stage to confront the comedian. Rock had his hands behind his back when Smith threw an open hand at his face that produced an audible smack.

Later, when accepting his first Oscar for best actor for his role in "King Richard," Smith apologised to the Academy of Motion Picture Arts and Sciences and his fellow nominees in a tear-filled speech, but not to Rock.

Now, people have dug into the internet archives and found that Smith is guilty of making a similar joke a few decades ago.

While tweets claimed that Williams, the man Smith joked about in the old clip, suffers from alopecia, it is unclear whether this is the case.

Nevertheless, this incident may cost Smith his sterling reputation in Hollywood, but not a criminal charge, at least for now, as Los Angeles police said Rock declined to file a police report.