By David "Los Gatos" Rosenberg

MGM Grand, Las Vegas - Floyd Mayweather Jr. (42-0, 26KOs) knocked out Victor Ortiz (29-3, 22KOs) in the fourth round to capture the WBC welterweight title. The ending had some controversy. In the fourth round, Ortiz had Mayweather backed up against the ropes and was throwing punches, but then used he intentionally fouled Mayweather with his head. Ortiz lost a point but then went over to hug Mayweather and touch gloves, when Ortiz backed away from the hug and looked for a split second at referee Joe Cortez, Mayweather unleashed two big shots to knock him out.

Mayweather doesn't believe there was anything illegal on his part. He says Ortiz used his head several times and busted open his mouth.

"This was another unbelievable performance. A lot of people want to know what happened.  There were a couple head butts.  Sh*t happens in the sport of boxing. Protect yourself at all times. You wanted to see a knockout and that is what I gave you. When Victor Ortiz was nine years old, I was dominating the sport of boxing," Mayweather said.

"I was always told to protect yourself at all times.  My mouth was split open. I said keep it clean.  Once you touch gloves, it is go time. We came together to fight. It is fight time. You want to do me dirty and then two minutes later you want to be my friend? This is the hurting business. Without the fourth round, he was going to get knocked out anyway.  I was fighting stronger. I was keeping my composure and sticking to the game plan.

"We were breaking him down. I listened to what my corner said. He was slowly breaking down as each round went. He was going to go anyway. Once you put me in that squared circle, I am home. I just say what goes around, comes around. Things happen in this sport and like I said, they say protect yourself at all times."