Former WWE Superstar turned UFC Fighter, CM Punk has responded to those who feel he has no place stepping inside the Octagon during an interview with SI.com:

"At the end of the day, it's about me and not anyone else. But, yeah, I used to not be able to read or walk or ride a bike or drive a car. Those people who are down on me trying this? Shut the f*ck up and don't watch the fight. ... The people who are mad or think this is an embarrassment to the UFC or the sport? I used to not be able to ride a bike. So when I was learning how to ride a bike, does Lance Armstrong come up to me and say: 'Who the f*ck are you, trying to learn how to ride a bike?' My attitude is punk rock across the board: Oh, you don't think I should do it? Well, I'm going to do it and I'm going to try to be the best I f*cking can."

Click Here to read the full interview.