It's rare to see sassy TV host Chelsea Handler look embarrassed -- usually, she's the one who's mocking other people. What could unnerve Ms. Handler? Well, a discussion of her rumored relationship with rapper 50 Cent did the trick. And it was Chelsea's own guest who turned against her.

Last week, Chelsea and 50 Cent were seen getting "hot and heavy" in a New Orleans bar. Handler has since denied on Twitter that she is dating 50 Cent -- but the rest of the world basically assumes that they are getting it on. On her show 'Chelsea Lately,' guest Jo Koy couldn't take it anymore -- and confronted her with the accusations. Chelsea had some trouble denying the rumors this time around.

Jo Koy said this to her: "Thank you for 'banging' 50 Cent, Chelsea." The host blushed, turning a deep shade of crimson. A few seconds before, she had been mocking Jo's bright red sweater -- now, the tables were turned. "Don't make me turn ... red," she said, laughing and pointing to her flushed cheeks. Chelsea again denied any relationship -- "I'm not banging him!" But her next statement was oddly contradictory: "When I have something to say, I will say it on this show." This seemed to imply that there was something to say, but that Chelsea didn't want to talk about it.