Here are some quotes from Sonnen's interview on UFC Tonight where he announced his retirement:

On his failed drug test: "When I woke up yesterday morning, I never would have had the foggiest idea that I was going to get notified that I had a banned substance in my system. These are not performance enhancing drugs, these are not illegal drugs and these are not steroids. They banned testosterone use in Nevada. Now I had to comply with that because I was a user. When you come off this you have to go through a transition phase. We were very transparent about that."

On if he takes responsibility for his failed test: "I absolutely take responsibility. When I spoke with Dana White yesterday, and he was on FOX Sports 1, he was very clear to say that Chael needed to talk to the commission. I agree with that. This was out of competition testing. I'm only the third athlete to go through this. There are some moving parts and a little bit of a learning curve. In the meanwhile, my wife and I were having problems with fertility. This is a matter of health and being a parent and this is a matter of being able to live in the next chapter of my life. At no point was there an attempt to slip around the system. I want to admit fault and accept full responsibility. Yesterday when this came out, I was mad. I was a fighter and I went in defense mode. However ultimately the rules are the rules and I'm a rules guy, I don't want to break the rules. And ultimately it comes down to the athlete to make sure he's in compliance."

On his retirement: "Guys, I've had a great time. I want to thank coaches Roy Pittman and Dave Sanville and I want to thank my coach Clayton Hires. These guys taught me how to fight and they taught me how to set goals and work hard and persevere, and they stood by me. I want to thank FOX and the leadership at UFC. I want to think Bill Brady, who gave me a second wind. He's a member of the Nevada State Athletic Commission and he believed in me when I really needed someone to believe in me. And I owe the second wind in my career to him. And I want to thank the single most important opponent I've ever had, I couldn't have gotten where I am without the dance partner, Anderson Silva. Thank you for the opportunity and the memories. Thank you for the invitation to the barbecue. I want to officially announce my retirement from competitive mixed martial arts."

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