Floyd Mayweather defeats Victor Ortiz with controversial fourth round knockout to claim the WBC welterweight title.
LAS VEGAS, NEVADA, UNITED STATES. (SEPTEMBER 17, 2011) REUTERS - Floyd Mayweather Jr took the WBC welterweight title from Victor Ortiz with a controversial fourth-round knockout on Saturday (September 17) that prompted an angry response from the crowd and raised questions about his conduct in the ring.
Ortiz had pinned Mayweather against the ropes before he was penalized by referee Joe Cortez for a head-butt. After a brief time-out, Ortiz apologized to his opponent in the center of the ring by touching gloves and Mayweather suddenly responded with a left hook and crunching right that dropped Ortiz to the canvas.
Boos rang out from the crowd in the MGM Grand Garden Arena but Mayweather, who improved his career record to 42-0 with 26 knockouts, started celebrating the knockout.
Mayweather then showered his post-bout interviewer with abuse and said he had never given him "a fair shake".
Fighting for the first time in 16 months, Mayweather had upped the pace early on in the fourth round with a flurry of body jabs and upper cuts.
Ortiz responded with a furious sequence of blows before pinning the challenger to the ropes.
Ortiz, who took the WBC welterweight title from Andre Berto in April with an unanimous points victory, slipped to 29-3-2 with 22 knockouts.