He also argued, correctly, that those who found the fight boring had missed Mayweather’s genius. Mayweather dipped under Guerrero’s punches, slid around Guerrero’s grasp, landed right-handed pot shots. It was clinical, surgical, efficient. It was artistic.

Ghost, busted.

Yet there were those afterward who argued that Mayweather ran from Guerrero. They argued that Mayweather picked another challenger he was certain he could beat. Mayweather cannot win that argument. His opponents are always too old or too green, too small or too slow. That is the perception, which conveniently leaves out or minimizes his superior athletic gifts.

One cannot defend the fact that Mayweather has not squared off against Manny Pacquiao — the best boxers of a generation, often in the same weight class, on paths to greatness that never intersected. The rest of his career — defensive fighter or not, knockouts or not, exciting fights or not — should be more celebrated, and it would be, too, were Mayweather not so caustic and divisive.

“There is an underappreciation of him, and I don’t quite get it,” Espinoza said. “When he wins convincingly, people revise history and say he didn’t fight a good opponent.

“He can’t win for winning.”

The news conference plowed onward. Mayweather climbed onto the stage in a purple sweatsuit, his hat adorned with “MAY DAY” in large gold block letters. He was asked if his opponents actually believed that they could beat him or if they were simply content to collect a seven-figure paycheck and parlay an expected loss into exposure. Victor Ortiz, for instance, went from being knocked out by Mayweather to appearing on “Dancing With the Stars.”

Someone asked Mayweather how he compared with history’s greatest boxers, with Sugar Ray Robinson and Muhammad Ali, Roberto Duran and Marvin Hagler and Sugar Ray Leonard and all the rest.

“I’m not here to match myself against them,” Mayweather said, even though he had often engaged in that practice in recent years. “I’m here to fight the fighters of my era.”