Former WWE Superstar CM Punk shocked the world last month when he announced he was signing with UFC and CEO Lorenzo Fertitta commented on the "Best in the World" making his debut in the Octagon.

Fertitta told ESPN.com that Punk's first fight, which is expected to come in six or seven months near the end of 2015, will be against someone "competitive" and will likely be a part of a co-main event on pay-per-view down the line.

Fertitta said that UFC may go outside the promotion to find an opponent for Punk, but he also added that UFC matchmaker Joe Silva will have the final say.

"I'm going to defer to Joe Silva. We'll let him bring two to three names to the table and we'll figure it out from there," Fertitta said. "But I guarantee you it will be a competitive guy."

Punk has been training hard and has some experience in mixed martial arts, so Fertitta expects him to have a solid opponent in his debut fight.

"I think it has to be somebody with some level of credentials," he said. "It's not just going to be some guy off the street. It's going to be somebody who is a professional mixed martial artist -- certainly somebody who MMA media will recognize and know."

Punk walked out on the WWE last January after the Royal Rumble and later talked about everything that led up to his departure on his friend Colt Cabana's Art of Wrestling podcast.

Punk blasted the WWE and said they tried to make him wrestle hurt after he suffered a head injury at the Rumble, while maintaining it wasn't the first time he had been asked to work with a severe injury. Punk also said that the WWE "stifled" him creatively ever since 2011 and he was fed up with it.

The "Best in the World" said he would never have a working relationship with the WWE again and eventually announced at UFC 181 in December that he signed with the promotion.

Punk is married to WWE Diva AJ Lee and she was by his side when he made the announcement despite her ties to the WWE. Lee is taking some time off from the organization right now and Punk revealed he received his termination papers from the corporation on the day they tied the knot.

Punk's UFC debut won't happen for a while, but many fans are interested to see who his first opponent will end up being.

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