DISAPPOINTED! WE'LL HAVE TO WAIT TO SEE FLOYD MAYWEATHER FIGHT AGAIN!

Floyd Mayweather Jr.'s long-awaited return to the ring will have to wait a bit longer after the six-time world boxing champion sustained a rib injury during practice last week, forcing the postponement of his July 18 fight with Mexico's Juan Manuel Marquez in Las Vegas.

Richard Schaefer, the president of Golden Boy Promotions, Mayweather's promoter, said he learned of the injury Sunday morning and won't have any information about a new date until Mayweather sees a doctor again this week.

"He just couldn't train, he couldn't move. It was very painful," said Schaefer, who added that the rib wasn't broken.

Mayweather retired undefeated, regarded as the best pound-for-pound fighter in the world, after a December 2007 victory over Ricky Hatton, then announced his planned return against Marquez last month. And Schaefer speculated Sunday that the long layoff may have contributed to his injury.

"If you are off and you know how tough of an [opponent] Juan Manuel Marquez is, you know that you have to train promptly, that you have to push yourself," he said. "If you have a well-oiled machine which fights every three, four, five months or so, that's one thing. But if you're off for a while, it certainly doesn't help the cause."

The fight, which was to be shown on HBO pay-per-view, was already suffering at the box office, where it was not attracting the same action as Mayweather's earlier fights with Hatton and Oscar De La Hoya. And the delay almost certainly takes the Mayweather-Marquez winner out of the conversation for Manny Pacquiao's next fight. Pacquiao was ringside at Madison Square Garden on Saturday to watch Miguel Cotto's split-decision victory over Joshua Clottey and was to meet with his team Sunday to discuss his next bout, with potential opponents now likely narrowed to Cotto and Shane Moseley.

Mayweather's Manager Leonard Ellerbe did not respond to messages seeking comment although the fighter issued a statement in which he said he was training hard and was disappointed with the postponement.

Marquez, who is training in Mexico, also expressed disappointment and said he "will remain focused, in shape and ready to fight whenever the fight is rescheduled."