As the above picture demonstrates using vaseline on your body is a big non no in combat sports. Apparently a corner man applied some vaseline to George St. Pierre's back between rounds one and two. The goods via cagepotato.com

B.J. Penn's camp has filed a formal complaint with the Nevada State Athletic Commission over Vaseline that was allegedly rubbed on Georges St. Pierre's back between rounds one and two. UFC president Dana White said at the post-fight press conference that he was aware of the complaint, and said he personally witnessed members of the commission take the Vaseline away from GSP's camp and rebuke them in the Octagon between rounds.

"I saw the commission jump up there and flipping out," said Dana White. They said one of the guys was rubbing Vaseline on Georges' back in between rounds. It was one and two, I think."

"The guys from the athletic commission went up there and started screaming at them. Knocked the Vaseline and kicked the Vaseline out of the Octagon."

I can't believe vaseline may taint this fight. B.J. Penn got his ass kicked regardless of any petroleum jelly, but this is still a rule violation and the NSAC should investigate. But I don't think when B.J. Penn's brother threw in the towel it was due to GSP being slippery as oppose to Penn getting absolutely destroyed. 

For those not familiar with Vaseline it is a petroleum jelly based product that is used in skin creams, lotions, cleansers, deodorants and lubricants. For those with dry skin it rejuvinates and moisturizes the skin. For those who are a little bit lonely it can 'lubricate' the evening. 

Still vaseline for the win.