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Joan Rivers was clearly one of the most hardworking stars in show business. Chris Rock opened up about meeting the late comedienne for the first time on what he considered to be "the worst day of her life" while attending the Toronto Film Festival on Saturday.

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"I did the very last 'The Late Show Starring Joan Rivers' on Fox. It was my first time on television," Rock recalled to Variety on when the two first rubbed shoulders. "Her show had just gotten canceled and her husband had just shot himself in the head. And for whatever reason, she decided to go and do the last show. Boy, did I learn about the show must go on that day."

"She had it together on camera. When we were on commercial, she was losing it a little bit," he continued. "I can definitely say I saw her start to cry. She kept it together."

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Rivers rose to fame when she did stand-up on several variety shows in the 1960s, and made her mark when she sat down with Johnny Carson on "The Tonight Show." The two had a famous falling out when Rivers had the opportunity to headline her own program from 1986 to 1987. (She was the first -- and still is -- only woman to host a late-night network show.)

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In the aftermath of her firing, her husband, Edgar Rosenberg, committed suicide in August 1987. She later spoke about the tragedy and her firing during her 1990 daytime Emmy speech. "[Thank you] especially to my daughter Melissa, because the last two years have been very difficult. Two years ago, I couldn't get a job in this business," she said at the time. "And my husband, as you know, had a breakdown. It's so sad that he's not here, because it was my husband Edgar Rosenberg who always said, 'You can turn things around.'"

Rivers died at 81 on Sept. 4, with funeral plans set for this Sunday at Temple Emanu-El in NYC. Several fans and celebrity friends have paid tribute to the E! "Fashion Police" host via social media and elsewhere, including Rock.

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"There's a weird thing that happens in art when you meet somebody and they are 30 years older than you. But if you last in the business long enough, one day you're the same age as your peers," the "Top Five" actor told Variety. "The last few years, I would bump into her and talk comedy. I just loved Joan Rivers. My family, we watched 'The Tonight Show' for Rivers. We liked Johnny Carson, but we loved Joan Rivers. I know I'm going to get [expletive] for that. But that's how it was in Bed-Stuy [Brooklyn]."


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