Floyd Mayweather Jr. is known to be a brash and confident boxer, in and out of the ring. The undefeated American is sticking with that persona when he boldly states that fans will support his bout against compatriot Andre Berto in September despite initial backlash — both from the fans and critics — for selecting the unheralded American for his next fight.

In an interview with Edward Chaykovsky of boxingscene.com, Mayweather said he expects boxing fans to buy the pay-per-view, valued at $64.95 and $74.95 for standard and high definition, respectively, of the Sept. 12 bout at the MGM Grand Arena in Las Vegas.

“They always tune in. They say one thing, but they do another.” Mayweather said while adding that the fight against Berto will be the last in his illustrious career.

Mayweather (48-0-0, 26 knockouts) is poised to retire from the game undefeated considering he will be an overwhelming favorite against Berto and is pegged to match Rocky Marciano’s 49-0 win-loss record.

Berto (30-3-0, 23 knockouts) has lost three of his last six bouts, most notably to Robert Guerrero in November 2012 in a battle for the interim World Boxing Council welterweight title. He was also knocked out against Jesus Soto Karass in July 2013 in the 12th round.

In the same interview, Mayweather admitted that he is seriously preparing for Berto, who is known for his activity atop the ring and potential knockout prowess.

"I don't know why, but I am training a lot harder for this fight,” Mayweather added. "I just want to go out with a bang, I guess.” Mayweather is coming off a largely unentertaining 12-round unanimous decision victory over Manny Pacquiao last May.