Floyd Mayweather knocked out Victor Ortiz in the fourth round to win the WBC Welterweight title Saturday night in Las Vegas.

The fight ended in controversy as Ortiz was deducted a point for an illegal headbutt. When the referee resumed action, Ortiz hugged Mayweather to apologize, then backed up with his hands down.

With Ortiz not mounting any type of defense, Mayweather caught him with the combination that ended the fight.

Mayweather had already built a big lead on the scorecards at the time of the stoppage. Ortiz had promised to come forward and look for the knockout, which fell right into the counter-punching Mayweather’s hands.

As the southpaw, Ortiz came forward, Mayweather caught him with right-hand leads throughout the four rounds. Ortiz had not yet found a way to avoid Mayweather’s right at the time of the stoppage.

Mayweather also displayed a clear advantage in handspeed over the younger Ortiz.

In the fourth, Mayweather stunned Ortiz with a combination early, and Ortiz charged forward with his most prolonged flurry of the night. He backed Mayweather into the ropes, although he was unable to land any solid punches through Mayweather’s guard.

While working on the ropes, Ortiz landed a headbutt to the face of Mayweather. Referee Joe Cortez called time and deducted a point from Ortiz for the illegal move.

When the fight resumed, Ortiz gave Mayweather a hug, kissed his cheek, then backed away.

Mayweather threw a left hook that stunned Ortiz, then dropped him with a straight right. Ortiz couldn’t beat the ten count, and the fight ended at 2:59 of the fourth.

Reaction to the ending was split. Mayweather received criticism for what many thought was a cheap shot. Ortiz said, “I was blindsided.”

On the other hand, Ortiz violated the first rule of boxing: Protect yourself at all times.

Afterward, referee Cortez said,

“Time was in, and the fighter has to have his guard up. Mayweather did nothing wrong.”

At the post-fight press conference, Mayweather was unapologetic, saying,

“(Stuff) happens in the sport of boxing. You wanted a knockout, and that’s what I gave you.”

Earlier, Mayweather had a run-in with Larry Merchant as the HBO announcer tried to do the traditional in-ring post-fight interview. Mayweather refused to speak to Merchant and told him, “HBO should fire you.”

Mayweather remained undefeated at 42-0. He recorded his 26th career knockout but first since stopping Ricky Hatton in 2007. It was his earliest knockout since a second-round stoppage of Angel Manfredy in 1998.

Mayweather regained the WBC title he won from Hatton. He vacated the title when he took a 21-month hiatus from the sport following that bout.

Ortiz took the title from Andre Berto in April of this year and was defending it for the first time. He lost for the first time since June, 2009, seven fights ago, and fell to 29-3.

On the undercard, Erik Morales won a world title in a fourth weight class, becoming the first Mexican fighter to do so.

He stopped last-minute replacement Pablo Cesar Cano on a tenth round TKO to win the vacant WBC Light Welterweight title

Morales was originally supposed to face Lucas Matthysse, but an illness forced him to withdraw less than a week before fight night.

Cano had a large cut by his left eye, and the doctors stopped the fight following the tenth round. Morales recorded his 36th knockout and improved to 52-7. Cano lost for the first time and stands at 22-1-1.