WWE Champion CM Punk is a legitimate fan of mixed martial arts, and it shows.  It shows so much in fact, that he was scheduled to walk out to the Octagon with UFC middleweight Chael Sonnen at UFC on Fox 2 in Chicago.  

However, once WWE chairman Vince McMahon learned exactly why Punk wanted the night off from a WWE house show, permission to attend was not granted.

Ariel Helwani of MMAFighting.com reports:

WWE champion CM Punk will not escort Chael Sonnen to the Octagon prior to Sonnen's fight against Mark Munoz on Jan. 28, after all.

Punk confirmed with MMAFighting.com that WWE chairman Vince McMahon decided against allowing him to walk out to the cage with Sonnen later this month. MMA reporter FrontRowBrian first reported the news Friday afternoon.

This is not a surprising turn of events, as the idea of both UFC and WWE brass being okay with this seemed peculiar from the start.  Although the companies aren't at one another's throats, there are obvious complications for a professional wrestler to appear with a legitimate fighter.  

The mere thought of a worked fight sends shivers down the spine of mixed martial arts fans, and CM Punk would represent that to many of them.  For Vince, it's hard to see him ever wanting one of his wrestlers on live television without complete control of the appearance. 

Will CM Punk ever get around to watching a major MMA event live in his hometown?  Chances are slim as long as he's holding the WWE championship.