For Kathy Griffin, Joan Rivers was more than just a dear friend — the late star was a fearless performer who paved the way for many future comediennes, including Kathy.

"No matter what she did, she had that fire in her eye. That's what you would see in the male stars [in the industry] as well, but it was a little unique to see it in a female star. She had the same kind of drive that the boys had," Kathy, 55, said of Joan in the upcoming documentary Joan Rivers: Exit Laughing.

joan rivers kathy griffin

Joan and Kathy in March 2011.

"What that said to me though the screen was, 'If I decide to [become a comedienne], I have to do what the boys do, and I'm pretty sure I'm going to have to fight three times harder. ' She knew she had to work harder, jump higher [than the men in this industry] — and she did," Kathy added, according to People.

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Joan sadly died in September 2015 at age 81 from cardiac arrest after undergoing a routine throat surgery. Following Joan's passing, Kathy took over as host of the late star's E! show, Fashion Police, but she later left the program in March 2015.