CM Punk's setbacks may not only be injury-related.

The former WWE Superstar signed with UFC in December 2014, but he has yet to make his debut.

The MMA promotion was originally hoping to have the "Best in the World" make his debut in the Octagon in the summer or fall of 2015, but shoulder and back injuries have forced him to delay his first fight.

It was announced that Punk would face relative newcomer and New Jersey native Mickey Gall in his UFC debut, but it was pushed back once the former WWE Heavyweight Champion had to undergo back surgery. It also appears Punk isn't progressing like he should be as he prepares for his first fight.

There are numerous accounts of Punk training, but not progressing in the way he should as an MMA fighter, according to Dave Meltzer of The Wrestling Observer (via Wrestlingheadlines.com). Meltzer notes that there have been consistent reports that Punk hasn't fared well during sparring sessions in the gym.

Punk underwent a similar surgery to Cain Velasquez, who had the procedure a couple of weeks prior to Punk, but is scheduled to fight at UFC 200 in Las Vegas on July 9. That means Punk shouldn't be too far behind, but since he's making his debut, he may need more time to train.

The former wrestler's first fight should generate a lot of buzz, but there are many who believe Gall will run right through him, according to the report. Punk is making his UFC debut at age 37, while Gall, 24, has been fighting through different circuits and won in his debut with relative ease.

Gall earned the right to face Punk in February, but hasn't had another fight since as he awaits the "Best in the World" to be ready. Gall views Punk as a "lottery ticket" since fighting and beating him would be a huge moment for him in his young career.

The MMA fighter hasn't taken Punk very seriously, but won't take another fight in the interim so that he doesn't risk missing his chance to beat Punk and move on to other fighters.

"Let me tell you, I hope it's soon. I think it's going to be this summer, which I can do. I can wait," Gall recently told the SFLC Podcast (per Fox Sports). "I'm training and I'm getting better and what I can't wait for is to get my fight with CM Punk, beat CM Punk and then get started with the UFC roster."

Hopefully that fight actually happens someday.

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