7. Undertaker
Less than two months after Punk defeated Jeff Hardy for the World Heavyweight Championship and sent the Charismatic Enigma packing to TNA, he would lose the title to the Undertaker. In his DVD, Punk says that he felt he had plenty of heat to carry the championship forward and that creative gave him a shrug when he asked about his direction, which confused and irritated him. Theres no mention of a rumor that Punk had heat because Taker tried to raise an issue with him about how he was dressed while he was champ during a European tour, and Punk pointed out that Cena dressed down too. Word got back to management, and shortly thereafter, Punk was jerking the curtain at Hell in a Cell and losing his title to the Undertaker. Now, Jim Ross refuted that rumor, and while the Taker title change is glossed over in the DVD, several talking heads make sure to mention how Punk gained Undertakers respect in the ring. And of course, four years later, Taker put his WrestleMania undefeated streak on the line against Punk, which shows a level of respect. While theres no confirmation of the story, stranger things have happened in pro wrestling, and titles have changed hands for lesser reasons, so theres a decent chance that Taker could have been taken aback at the upstart Straight Edge Superstars attitude.