Jerry Seinfeld Was Planning a Special Project With Joan Rivers

He'd been working on a project with Rivers, whom he called "one of the greats."

— -- Jerry Seinfeld was planning a special project with Joan Rivers.

Before her Sept. 4 death, Rivers was in talks to appear on Seinfeld’s popular web series “Comedians in Cars Getting Coffee,” Seinfeld revealed in a Facebook post. The series features Seinfeld making coffee trips with friends and entertainment figures.

Seinfeld posted a text message exchange from Aug. 19 – nine days before Rivers underwent a throat procedure – stating that Rivers would love to participate.

READ: What We Know So Far About Yorkville Endoscopy and Rivers' Death

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But days later, her reps called, saying Rivers needed to postpone.

Rivers went into cardiac arrest during surgery Aug. 28 and died days later. She was 81.