Mayweather's 49th bout could end with a whimper

The 38-year-old insists this is the last fight of his stellar career

LAS VEGAS: Should Floyd Mayweather Jr. end his boxing career on Saturday as promised with his welterweight title defence against fellow American Andre Berto, he could well sign off with a whimper rather than a bang.

In stark contrast to his previous fight, the much hyped mega-bout with Manny Pacquiao four months ago, the build-up to Mayweather's 49th appearance in the ring as a professional has lacked buzz and plenty of tickets are still available.

Mayweather, 38, has faced criticism from fight fans who say he ducked some of the best in the weight division in cherry-picking Berto, who is a massive underdog.

Britain's Amir Khan was among a host of fighters who wanted a go at pound-for-pound king Mayweather.

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Mayweather's critics accuse him of attempting to drum up badly needed interest by declaring Saturday his swan song but it threatens to be a box-office flop with hundreds of tickets still widely available at the MGM Grand on Wednesday.

In May, Mayweather earned more than $200 million from his so-called "Fight of the Century" with Pacquiao that became boxing's richest ever showdown.

Against Berto on Saturday, Mayweather has settled for a reported $32 million. The appeal of Saturday's bout at the MGM Grand Garden Arena, which will be televised on pay-per-view for a suggested price of $74.95, has clearly not been helped by Mayweather's choice of opponent, Berto having lost three of his last six fights.

"I just try to stay positive, keep my fingers crossed and hope for the best," undefeated five-division world champion Mayweather said of the slow ticket sales while preparing for what he has repeatedly claimed will be his swansong in the ring.

"Nobody's forced to watch. Watch if you want to watch. If you don't want to watch, don't watch."

Mayweather, the world's highest-paid sportsman, told a press conference, pointing out that Berto had twice been world champion.

"Berto is not a pushover. No matter who I choose, the media will have something to say,"

"Khan has three losses, Berto has three. No matter what the media say, when it comes down to it, it is two competitors and I know what I can do.

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"I can fight. When you talk about highest gates, I am that guy. Highest (television) pay-per-view, I am that guy."

Mayweather, wearing green shirt and sun glasses, also defended what he called his "remarkable" 19-year career.

"I keep my eyes on the prize and never focus on the outside. I focus on the guy in front of me," added Mayweather, heralded by some as the best boxer of his generation.

"I push myself. I believe in my skills and talent," he said. "I have been in there with the best and the result is always the same.

"I always had a dream and my dream was to be the best. No matter what happens on Saturday, when it comes to boxing, I am the best there is."

Both men say they will go for the big knockout and Berto (30-3, 23 KOS) said it was all about "respect."

"When it comes to the media, the critics... they are not in that gym busting their asses. They don't know the sacrifices we have to make. A few select people can do that," said Berto, 32, whose career has been knocked sideways in recent years by injury and a failed drugs test.

"There are small whispers of negativity from people that could not dare to do what we do."

He added: "When it comes to fight time I am coming for my respect."