By Mark Lamport-Stokes
LAS VEGAS (Reuters) - The 'will he, won't he?' doubting game continues as Floyd Mayweather Jr. prepares for what he has said will be the final fight of his career while most boxing pundits shrug their shoulders in disbelief.
Five-division world champion Mayweather will defend his WBC and WBA welterweight titles against American Andre Berto at the MGM Grand Garden Arena on Saturday and throughout the build-up he has repeatedly insisted that this will be his swansong.
However, Mayweather has long been a consummate self-promoter and the doubters can point to the American's unexpected U-turn when he came back from a 21-month retirement to fight Mexican Juan Manuel Marquez in September 2009.
Should Mayweather win on Saturday, as is widely expected, he would match the 49-0 record of former heavyweight great Rocky Marciano and it would seem most unlikely that he would not be tempted to return to the ring for a 50th fight.
"I came to say I'm going out 49-0," Mayweather told reporters while preparing for Saturday's scheduled 12-round bout. "I'm happy with how my career went. Number 49 is my last fight."
Asked whether he might 'get that itch' to come back for another bout, as he did in late 2009, Mayweather replied: "No, I'm going to just push the limit for this fight and see what I can accomplish.
"My health is more important. If you stick around anything too long, anything can happen. You can make a lot of money, but you still want to be able to talk, walk, and have a sharp mind."
Stephen Espinoza, executive vice president of cable giant Showtime Sports whose lucrative six-fight deal with Mayweather will end with the Berto bout, was initially doubtful but he now believes that the American will call it quits on Saturday.
"Like many people, I had my doubts about whether this would be his last fight," Espinoza told Sports Illustrated. "I say that in the past tense because over the course of the last four weeks, I've changed my mind.
"I hear the tone of his voice and the way he sounds and some of the very candid concerns has has voiced about his own health.
"I think that he's sincerely reached a point where he sort of feels like he has done everything that he needs to do in the sport."
However Mayweather's trainer and father, Floyd Mayweather Sr., expects his 38-year-old son to to fight again, though he has cautioned him to make a decision for no more than six months after Saturday's fight because of his advancing age as a boxer.
"I can't say he won't quit and then come back," Mayweather Sr. told the New Jersey Star-Ledger. "I fought too may fighters, trained too many fighters, watched too many fighters not to know how many of them do come back -- a year later, two years later.
"If he thinks it over and he wants to go after that Marciano record, I'm sayin', 'I don't think he needs it.' But if he thinks he does, there is just one way to do it.
"That's to go do it right away. Don't wait and be out there a year or two later ... rusty, reflexes gone ... because that's the way it happens. If my son (is) gonna fight any more, I hope he fights in five or six months."