LAS VEGAS – The countdown to the end of Floyd Mayweather Jr.'s legendary career began on Saturday with a brilliant performance in a victory over Robert Guerrero at the MGM Grand Garden.
Mayweather rolled his record to 44-0 and kept alive a dream to end his career with a perfect mark.
He signed a six-fight, 30-month contract with Showtime in February – likely his final contract – and he started it off on the right foot.
He won a unanimous decision, with all three judges seeing it 117-111, to keep his WBC welterweight title.
Though Guerrero's trainer and father Ruben Guerrero shouted at the conclusion, "He ran like a chicken, baby," it was a masterful boxing performance by Mayweather.
Guerrero tried to pressure Mayweather, but Mayweather had none of it. Guerrero had some success pinning Mayweather in the corner in the first two rounds, but after that, Mayweather used his lateral movement and a laser accurate right hand to pummel Guerrero.
He landed more than 60 percent of his power punches and was never in danger. Only Guerrero's solid chin kept him from being stopped. He repeatedly took clean, hard shots from Mayweather.
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Mayweather said he was injured in the middle of the fight, but he didn't show it.
He landed 195 of 476 punches and landed 153 of 254 power shots.
"I don't remember what round it was, but I hurt my right hand," Mayweather said.
Mayweather rarely took two punches in a row during the fight and was able to spin away or duck under trouble. He reunited with his father, Floyd Mayweather Sr., and brought back the defensive brilliance that his father preaches.
"My father always talks defense first," Mayweather said.
Guerrero praised Mayweather for his performance.
"That's why he's the best," Guerrero said, shaking his head.
Guerrero said "he was slipping by the britches," and noted that Mayweather was very difficult to hit.
It wasn't one of Mayweather's classic performances, but that probably was not that much of a surprise given he was coming off a 57-day stint in the Clark County Detention Center on a domestic violence charge and hadn't fought in a year.
But if that was Mayweather at less than his best, it showed how great he is because he routed a quality fighter on Saturday.
Guerrero landed just 113 of 581 punches overall, and had dozens of his punches picked off or blocked by Mayweather.
"Give him credit," Guerrero said.
Unless he moves up in weight, there aren't a lot of great challenges to Mayweather remaining, particularly if he gets past a likely bout with Canelo Alvarez. Alvarez defeated Austin Trout on April 20, and a bout with Mayweather is likely the biggest pay-per-view bout that can be made.