Floyd Mayweather resisted a furious early onslaught by fellow American Shane Mosley to preserve his unbeaten professional record with an unanimous points victory in a welterweight bout Saturday. Widely regarded as the best defensive fighter of his generation, Mayweather dominated 11 of the 12 rounds with his lightning hand speed and agile movement to improve his career record to 41-0 with 25 knockouts. A 4-1 favorite going into the highly anticipated bout at the MGM Grand Garden Arena, Mayweather was stunned by a flurry of punishing blows from Mosley in the second round. He remained undefeated but not before giving his fans and his corner a scare when a right hand to the side of his head buckled his knees a minute into the second, and he had to grab Mosley to avoid going down. Mosley landed another right later in the round, but the rest of the night belonged to Mayweather. Asked how he had recovered from Mosley's early onslaught, Mayweather replied: “It's a contact sport and you're going to get hit. But when you get hit, you've got to suck it up and keep on fighting. And that's what I did.” The flamboyant American gained one-sided verdicts from all three judges – 119-109, 119-109 and 118-110. WBA welterweight champion Mosley, who had not fought since a ninth-round TKO upset of feared Mexican slugger Antonio Margarito in Jan. 2009, slipped to 46-6 with 39 knockouts. The bout was watched by a crowd of around 16,000 that included Hollywood actors Will Smith and Leonardo DiCaprio and boxing greats Muhammad Ali and Sugar Ray Leonard. Mayweather dominated the official ringside statistics, connecting with 208 of 477 punches thrown to 92 of 452 for Mosley. Mayweather also landed 123 power punches compared to Mosley's 46. No Pacquiao fight without blood, urine tests Mosley was a substitute for Manny Pacquiao, who was all but signed to meet Mayweather until a dispute over drug testing derailed the megafight. Instead, Pacquiao beat Joshua Clottey on March 13 in Dallas and is now campaigning for a seat in congress in his native Philippines. “If Manny Pacquiao can take a blood and urine test then we have a fight,” Mayweather said. “If not, no fight.” Mosley agreed to the tests in order to make the fight with Mayweather happen. Huck defends title Germany's WBO cruiserweight world champion Marco Huck defended his title for the third time after challenger Brian Minto was forced to retire at the start of the tenth round at Oldenburg, Germany, Saturday.