Following a failed out-of-competition drug test that revealed banned substances in his system, UFC middleweight Chael Sonnen announced on Wednesday that he is retiring from professional mixed martial arts. The fighter made the announcement on UFC Tonight during his weekly role as the FOX Sports 1 program's co-host. “I want to stay within the rules, and I don't fully understand them, and I have to put my health first. I have to put my family first,” Sonnen said. “There's going to be a day where I no longer have the title of fighter,” he added, “but I don't ever want there to be a day where I don't have the ability to have the title as parent and father and husband, and my health has got to come first.” Yahoo.com