ENTERTAINMENT on Instagram: "The Mayweather Jr. vs. Victor Ortiz fight on September 17, 2011 at the MGM Grand delivered one of the most controversial moments in boxing history. Ortiz, newly crowned WBC welterweight champion, tried to pressure the undefeated Mayweather but stunned everyone when he intentionally head-butted him in the fourth round. After the referee deducted a point, Ortiz kept apologizing—arms down, guard wide open. In that split second, Mayweather fired two razor-sharp punches,