LAS VEGAS—Floyd Mayweather Jr. spent Saturday night doing — for the most part — what he’s done in the vast majority of his championship bouts over the last decade.He fought strategically. He landed counterpunchers. He held to offset rallies.The significance of this one was that the opponent was Manny Pacquiao.In a welterweight bout that’s seemingly been a generation in the making, Mayweather controlled the action in mid ring, eluded prolonged damage along the ropes and worked his way to a unanimous decision that earned him the WBO welterweight title to go along with the WBA and WBC belts he arrived with.The win boosted him to 48-0 as a pro in a 19-year career. Pacquiao is 57-6-2.Judge Dave Moretti gave it to Mayweather by a lopsided 118-110 count — which translates to 10-2 in rounds — while judges Glenn Feldman and Burt Clements each had it 116-112, or 8-4 in rounds.A partisan Pacquiao crowd booed the verdict.

“He’s a helluva fighter and I take my hat off to Manny Pacquiao,” Mayweather said. “Now I see why he’s one of the guys at the pinnacle of boxing. I fought a smart fight. I stayed outside. We did what we had to do tonight. When the history books are written, it will be worth the wait.”

Showtime’s Jim Gray asked Mayweather if he planned to continue and he said, “I’m fighting in September. Yes. My last fight is in September. I’m almost 40 years old now. I was 19 years old when I started.”

Mayweather was successful, as he’s been in other fights, at keeping Pacquiao’s aggression to a manageable pace. The Filipino was caught by a number of stiff right hands, but neither fighter ever appeared in serious trouble. Pacquiao had the most success when he was able to keep Mayweather along the ropes, which didn’t happen often.