Chael Sonnen Officially Announces His Retirement, Thanks Anderson Silva

"The American Gangster" is leaving the building. Chael Sonnen announced his decision to retire, and not fight his impending suspension, during "UFC Tonight" Wednesday evening. Sonnen failed a drug test recently, but continued to claim innocence in subsequent interviews.

"I want to officially announce my retirement from competitive mixed martial arts," Sonnen said. "I have to put my health first. I have to put my family first."

Sonnen (28-14-1) was a three-time challenger to UFC gold, falling twice to Anderson Silva for the middleweight belt and once to Jon Jones for the light heavyweight title. He was defeated by Rashad Evans in his most recent appearance, and was scheduled to meet Wanderlei Silva before Silva was removed due to a failed drug test.

Officials moved quickly, placing Vitor Belfort against Sonnen for UFC 175 in July. However, Sonnen was found to have two banned substances in his system during a drug test given to him by the Nevada Athletic Commission recently.

Instead of trying to fight the decision, which he stated on Tuesday he would do, Sonnen put an end to his fighting career. He and his new wife are expecting their first child, and he is likely to remain a vital part of FOX Sports' MMA programming moving forward.

Sonnen admitted during the segment that he takes complete fault for the failed drug test, and also put plenty of praise on Silva, calling him "the single-most important opponent I've ever had."

"I couldn't have gotten to where I am without this dance partner," Sonnen said. "That is you, Anderson Silva. Thank you for the opportunity. Thank you for the memories. Thank you for the invitation to the barbeque, even though I didn't take you up on it."