LAS VEGAS – Floyd Mayweather, said Richard Schaefer on Tuesday as he looked across a large crowd that had gathered in the lobby of the MGM Grand specifically to catch a brief glimpse of the world’s best boxer, is a details man. The chief executive officer of Golden Boy Promotions, Schaefer said there are few details of a business deal that escape Mayweather’s eagle-eyed scrutiny.

Floyd Mayweather Jr. is as focused on the business of boxing as he is on punching. On this day, the people had crowded around a makeshift boxing ring erected in the lobby to help promote Mayweather’s welterweight title fight Saturday on Showtime Pay-Per-View in the Grand Garden Arena against Robert Guerrero.

When he bolted HBO for Showtime in February and signed his historic six-fight, 30-month deal, a contract that could net him more than $250 million, he bargained fiercely to gain absolute control. But at 36, he knows he’s closer to the end than he is to the beginning. Some day, there will be a new star in boxing. Part of his goal over the next several years, he said, is to bolster the sport for the next generation.