During an appearance on Watch What Happens Live, Messing decided to kiss and tell, bringing it back to her time starring on Will and Grace.
A caller asked her to name the best and worst guest stars on the sitcom, and Messing's answer was surprisingly candid.
She said Harry Connick Jr., who played Grace's husband Leo Markus on the show from 2002 to 2006, was her favorite. And when WWHL host Andy Cohen suggested Bobby Cannavale, who played her character's love interest Eric McCormack, might be her least favorite, Messing shot it down with an even more shocking replacement.
"Oh my god, are you kidding? No! We loved each other," she revealed. "You know who, at the time, I wasn't a fan of? Jeremy Piven."
Piven appeared on the show in Season 3 as Grace's ex-boyfriend, who wants her to get in on a threesome. She almost goes through with it but backs out at the last second.
Messing explained why Piven was one of her least favorites and, after hearing the story, we don't blame her. "You know, I had to kiss a lot of boys on that show. And we were rehearsing, and the very first day of rehearsal, he shoved his tongue all the way down to my heart."
Messing said his attitude was just as forward as his kissing. "I was just like, 'Whoa!' He goes, 'Yeah, yeah,'" she explained. "He was like, 'That's it, I'm in.' I was like, 'You know, this is comedy. We don't really go that deep.' And every time, he went for it."
Piven, who is busy promoting the new Entourage movie, has yet to comment on Messing's hilarious throwback to his kissing skills.
Check out the full clip below.
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