Try to picture Robert De Niro gleefully dancing on a giant floor piano in New York’s FAO Schwartz as Josh Baskin in “Big,” the character unforgettably portrayed by Tom Hanks in the classic 1988 comedy.

It could have been.

The “Raging Bull” star, 77, was asked by “The Tonight Show” host Jimmy Fallon to confirm if he had been originally cast as Baskins, a young boy whose wish to turn into an adult comes true.

“Yes.” De Niro said. “But we had a thing, an issue, with the negotiation, so it went the way it went.”

“But that was fine,” De Niro added.

The story of De Niro’s casting in the Penny Marshall-directed comedy has been long-discussed and resurfaced most recently when “Big” star Elizabeth Perkins, who played Josh’s love interest Susan Lawrence, spilled the beans on “Watch What Happens Live with Andy Cohen” in April.

Perkins said she auditioned for the part with De Niro, who would have brought a very different character.

“He was more moody, it was a little bit of a horror movie. It was Robert De Niro wandering around the streets of New York,” said Perkins. “What Tom Hanks brought to it was so much lighter.”