Following the bombshell this week that CM Punk had reportedly quit the WWE, reports of an argument between the "Straightedge Superstar" and WWE CEO and Chairman Vince McMahon backstage during the preparations for last Monday's episode of RAW have been reported, leading to Punk quitting the company and walking out.

While details remain sketchy, according to Wrestlingheadlines.com, there have been reports that Punk got into a heated exchange with officials backstage involving concussions after it was believed that he was banged up during Sunday's Royal Rumble pay-per-view event in Pittsburgh.

Punk came into the match at No.1 and lasted until near the end of the match, leaving it banged up. Punk apparently passed all of the concussion tests and did not have a concussion though. The report also indicates that Punk's decision to walk out on the company had nothing to do with the concussion tests and it was strictly frustration and burn out that caused him to leave.

Punk reportedly met with McMahon at 7:30 p.m. before RAW went live and the show was re-written 10-11 times, including having the Kofi Kingston vs. Alberto Del Rio match last longer than scheduled to make up for the time that was allotted for Punk's written segment.

ESPN Cleveland reporter Casey Kulas was on scene and gave a description of the events backstage via Twitter:

Punk has expressed his frustration in the past couple of WrestleManias with returning stars coming back and taking the main event spotlight at the biggest show of the year while younger stars and wrestlers that work all year round don't get a chance to shine on the biggest stage of the year.

Punk noted The Rock main eventing the last two years frustrated him and he was angry over being sauntered down the card for a match with The Undertaker at last year's WrestleMania XXIX and while he said he likes Batista, he appeared angry that he will be headlining this year's event after a four-year absence.

Punk appeared at a Wizard World Q&A session over the weekend in Oregon and discussed his frustrations. He also addressed the rumors that Sting may come to the WWE and said that he shouldn't come over since he doesn't have much left in the tank and he'll again detract from the younger stars, according to Wrestlingheadlines.com.

Punk, who was under contract in July but was expected to leave after it expired rather than walk out last Monday, said the WWE is out of touch with what the fans want and that he has enough money now that he doesn't need to rely on a paycheck.

Punk is still being advertised for the WWE's Elimination Chamber event but will likely be pulled soon. Wrestlingheadlines.com reported that Punk was described by one source to be "as good as gone" from the WWE come July when his contract expired and another one hinting they'd be surprised if he lasted that long, which eventually became the case. Sheamus is set to replace Punk as the top star on all of the live events he was advertised for.

While a lot of people still claim it's a work, it looks like Punk has legitimately left the company.