LAS VEGAS - The pressure of a $180-million payday never got to Floyd Mayweather Jr., even if the richest fight ever wasn't the best.
Using his reach and his jab Saturday night, Mayweather frustrated Manny Pacquiao, piling up enough points to win a unanimous decision in their welterweight title bout. Mayweather remained unbeaten in 48 fights, cementing his legacy as the best of his generation.
After the fight, it was disclosed Pacquiao injured his right shoulder in training and Nevada boxing commissioners denied his request to take an anti-inflammatory shot in his dressing room before the fight.
Pacquiao chased Mayweather around the ring most of the fight. But he was never able to land a sustained volume of punches, as Mayweather worked his defensive wizardry again.
Two ringside judges scored the fight 116-112, while the third had it 118-110. The Associated Press had Mayweather ahead 115-113.
"I take my hat off to Manny Pacquiao. I see now why he is at the pinnacle of boxing," Mayweather said. "I knew he was going to push me, win some rounds. I wasn't being hit with a lot of shots until I sit in a pocket and he landed a lot of shots."
The bout wasn't an artistic triumph for either fighter, with long periods where both men fought cautiously.
Pacquiao threw far fewer punches than he normally does in a fight, with Mayweather actually throwing more.
That was largely because Pacquiao didn't throw his right hand often. Promoter Bob Arum said Pacquiao injured his shoulder sometime after March 11.
Arum said Pacquiao's camp thought he would be allowed the anti-inflammatory shot because he had gotten them during training and they had been approved by the U.S. Anti-Doping Agency. But he said paperwork filed with the commission didn't check the injury box, and the Nevada commission ruled against the request for a shot.
"The ruling made tonight affected the outcome of the fight," Arum said.
Nevada Athletic Commission chairman Francisco Aguilar said Pacquiao's camp wanted shots that included lidocaine, a drug that numbs the affected area. But he said Pacquiao's representatives didn't check the injury box after the weigh-in Friday, and the commission had no way of knowing how serious the injury was or what it could be treated with.
"I have no proof an injury actually exists and I can't make a ruling based on what they're telling me," Aguilar said.
Still, Pacquiao thought he had won the bout, largely on the basis of a few left hands that seemed to shake Mayweather.
"I thought I won the fight. He didn't do nothing except move outside," Pacquiao said. "I got him many times."
There were no knockdowns, and neither fighter seemed terribly hurt at any time. Pacquiao landed probably the biggest punch in the fight in the fourth round - a left hand that sent Mayweather into the ropes - but he wasn't able to consistently land against the elusive champion.
The fight was a chess match, with Mayweather using his jab to keep Pacquiao away most of the fight. Pacquiao tried to force the action, but Mayweather was often out of his reach by the time he found his way inside.
"He's a very awkward fighter, so I had to take my time and watch him close," Mayweather said.
Mayweather fought confidently in the late rounds, winning the last two rounds on all three scorecards. In the final seconds of the fight he raised his right hand in victory and after the bell rang stood on the ropes, pounding his heart with his gloves.
"You're tough," he said to Pacquiao, hugging him in the ring.
Mayweather said his fight in September against a yet-to-be-determined opponent would be his last.