This past weekend of 'Saturday Night Live' offered up a mixed bag  of laughs from host Eli Manning, and a similarly shrug-worthy turn of performances from pop diva Rihanna, but far more interesting is the behind-the-scenes tale.  Apparently, Rihanna managed to piss off some of the 'SNL' bigwigs in a serious way, but what could she have done?

According to TMZ, Rihanna's failure to show up for a crucial dress rehearsal prior to her performance greatly irritated 'SNL' boss Lorne Michaels, who places a great deal of importance on the rehearsals.  Purportedly "Rihanna was sick and needed to save her voice for the live show," even going as far as bringing a doctor into her dressing room, who administered a shot of penicillin prior to the show.

Rihanna's choreographer performed the dress rehearsal in her place, but the real trouble began when Rihanna herself finally appeared, as TMZ notes:

When Rihanna showed up later looking just fine, we're told the staff was shocked...and felt she didn't appear sick enough to have missed the dress rehearsal...though no one from the show called her on it.

According to our sources, once the live show got going, Rihanna was seen eating an apple and walking around in between songs...which bothered several staffers because she did not seem ill at all. We're told producers can't even remember the last time someone has skipped the dress rehearsal.

The performances went off without a hitch, as you can see from the videos below, but something tells us Lorne Michaels won't be too keen to bring Rihanna back onto the show for a little while.  What do you think?  Did Rihanna look sick at all during the performances?  How was the rest of the episode?  Give us your reactions in the comments!