Then, he said, "all of a sudden it turned into one of those Maury Povich paternity test shows."
He joked, "It was the weirdest TV finale since 'Lost.'"
"In other words, Clyde threw Bonnie under the bus," he quipped.
"We're sitting there and you kind of figure, well the host will go on stage and clear this up and then I remember, 'Oh I'm the host!'" he said.
By the time Kimmel returned to the stage, "La La Land" producer Jordan Horowitz had already corrected the mistake, announcing that "Moonlight" was in fact the winner for best picture.
"I'm feeling really bad for these guys, but also trying really hard not to laugh," Kimmel said.
"Eventually I figure out that Barry Jenkins, the director of 'Moonlight,' is standing behind me and Denzel wants me to get him to the microphone to make a speech, which makes sense," Kimmel said. "Thank God Denzel was there to make sense."
Jenkins did speak, followed by another quick speech from his producer.
Then, Kimmel said, "everyone just stood there shell-shocked, so I ended the show."
That's when people came up to him and asked if this had been one of his infamous pranks.
"I did not pull a prank," Kimmel told his talk-show audience. "If I had pulled a prank, by the way, I wouldn't just have the wrong winner's name in the envelope, there would have been a Bed Bath and Beyond coupon in there."
As it turns out, the biggest gaffe in Oscars history was neither Dunaway or Beatty's fault.
A partner from PricewaterhouseCoopers, the accounting firm which tabulates the votes and is responsible for handling the results, handed the wrong envelope to the two presenters. The firm apologized to the teams from "Moonlight" and "La La Land," Beatty and Dunaway and Oscar viewers.