A combo of file pictures shows World boxing champion Manny Pacquiao of the Philippines (L) before the successful defence of his WBO welterweight title in Dallas on March 12, 2010 and Floyd Mayweather Jr. (R) before his super welterweight title fight in Las Vegas on May 4, 2007.  Pacquiao announced on May 12, 2010 that he wanted to face Floyd Mayweather for his last professional fight after launching a political career in the Philippines. A Pacquiao-Mayweather clash, which US promoter Bob Arum said could take place on November 13, 2010 in Texas or Las Vegas, would likely generate one of the biggest purses and television audiences in boxing history.  AFP PHOTO / Chris Cozzone / Robyn BECK (Photo credit should read Chris Cozzone/AFP/Getty Images)