Ever since former WWE Superstar CM Punk announced he will be joining UFC on Saturday at UFC 181, there has been a lot of speculation as to who he will face in the octagon and when he will make his debut. Former UFC star Chael Sonnen said he believes he knows who the "Best in the World" will take on first.

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Sonnen spoke to MMAMania.com and said he had a "pretty good" idea who Punk will fight when he makes his UFC debut, but said he is going to keep it to himself.

"I'm going to keep that close to the vest," Sonnen told the site. "It would not make sense to give him a bottom-tier guy. Well he is not a bottom-tier guy, I can tell you that. You will know who he is and he will be a pretty-heavy favorite to win. Punk is not going to come in as the favorite."

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Sonnen also said he didn't think that Punk has made it a goal to climb up the MMA ranks.

Regarding Punk's training for his eventual UFC debut, King Mo posted a picture of the two working out alongside Rener Gracie and Roy Nelson on his official Twitter account:

WWE Superstar Chris Jericho, who took no issues with Punk's claims on Colt Cabana's Art of Wrestling podcast that Jericho wanted him on his Talk is Jericho podcast for publicity reasons, spoke about the possibility of Punk ever returning to the ring.

"That is something you will have to ask CM Punk, I haven't spoken to him about it," Jericho told Wrestling101 about Punk ever returning to the WWE. "I do know in 2005 I was very burned out from wrestling and I left for two and a half years. If Punk does come back it might take a while because when you're burned out your done, like I said it took me two and half years before I decided I wanted to come back."

He added: "A lot of people forget that I left for quite a long period of time. It is a tough life, there is a lot of pressure and a lot of politics, you go through a lot of s--t. If you're not there 100 percent it can really drag you down that's for sure."

Punk revealed Saturday night in Las Vegas that he will be joining the UFC and president Dana White said he expects Punk to make his debut in six or seven months. Punk has received a lot of criticism from many different fighters, but current UFC star Cole Miller recently had a message for his haters on Twitter:

The "Best in the World" walked out on the WWE in January and received his termination papers on the day of wedding to WWE Diva AJ Lee.

Punk and the WWE are on bad terms and things are likely only going to be worse between them now that he has signed with UFC.

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