LAS VEGAS -- Floyd Mayweather Jr. entered with a circus.
Marcos Maidana almost left with a parade.
In a fight that was supposed to be lopsided but turned out to be the toughest fight of his remarkable career, Mayweather beat Maidana via majority decision in a welterweight world championship unification bout.
"It was a tough, competitive fight, what the fans want to see," said Mayweather (46-0, 26 knockouts). "Normally, I box, I move, I blow the guys out. This time I wanted to stand there and fight."
Asked whether he would give Maidana (35-4, 31 KOs) a rematch, Mayweather said: "If the fans want to see it again, we'll do it again."
Maidana, a 10-to-1 underdog, said: "I definitely think I won this fight. Floyd did not fight like a man like I expected him to. ... Other fighters respected him and didn't go toe to toe like I did."
Mayweather's entrance was a spectacle, complete with a ring master announcing his arrival into the arena, dancing clowns and fake money fluttering down from the ceiling. He slowly made his way to the ring with Justin Bieber and rapper Lil Wayne walking a step behind him.
In the opening round, the brawling Maidana attacked, pinned Mayweather on the ropes and fired clubbing overhand rights. Not all shots landed, but the large contingent of Argentine fans roared their approval.
Maidana continued that strategy in the second, with Mayweather covering up and scoring on counterpunches. It's typical of Mayweather to spend the first couple of rounds measuring his opponent.
In the fourth round, Maidana opened a cut over Floyd's right eye, the first time he has been cut in his career, according to Showtime analyst Al Bernstein. The cut was caused by what the referee called an accidental head butt.
Mayweather battled back in the sixth and seventh rounds, coming alive with a few powerful uppercuts and lead right hands when he moved the fight to the middle of the ring.
In the eighth, Maidana continued his relentless assault, and at one point angered Mayweather with a low blow. Mayweather was accurate and effective when he threw punches, but he was mostly on defense.
In his corner, Maidana's trainer Robert Garcia told him to "be dirty if you have to."
In the ninth, Mayweather made a rare switch to left-hander and stung Maidana with a beautiful right cross. Maidana, so aggressive early in the fight, appeared to be running out of gas. His most effective defense was a good jab that kept Mayweather at bay.
Through 10 rounds, the punch count was remarkably close, with Mayweather landing 190 and Maidana 189.
Mayweather was crisp in the 11th round, patiently waiting for Maidana to allow an opening, then strategically picking him apart. At one point, the fighters clenched, fell over and partly through the ropes.
In the final round, the fighters stood toe to toe trading blows, and, not surprisingly, both raised their hands in triumph when it was over.
There was talk Friday that Mayweather-Maidana wouldn't happen because of a dispute over the gloves Maidana wanted to use.
Mayweather balked at the custom-made gloves Maidana had selected. A fighter's gloves must be approved by his opponent, as well as the Nevada State Athletic Commission.
Both the Mayweather camp and the commission objected to the distribution of padding in the gloves, arguing there was too much weight in the wrist area and not enough padding on the knuckles.
Several hours before the fight, the dispute was resolved. Maidana, who had wanted to wear blue Everlast gloves that matched Argentina's flag, agreed to wear stock black-and-yellow Everlast gloves. Everlast Chief Executive Neil Morton told Yahoo Sports that the custom and stock models of that glove are identical.
In an undercard bout, Norwalk's Carlos Molina lost to Adrien Broner by unanimous decision for the World Boxing Assn. international super-lightweight title.