( CNN ) -- Manny Pacquiao is aiming to deliver a knockout blow to Floyd Mayweather Jr. in the U.S. courts after filing a lawsuit against the American and his connections over claims he used performance-enhancing drugs . The lawsuit , lodged in the Las Vegas district court on Wednesday , names Mayweather , his father Floyd senior , former boxing star Oscar De La Hoya and fellow Golden Boy Promotions executive Richard Schaefer . `` Calling a professional athlete a cheater is the most serious charge one can make , '' the lawsuit says , `` and in today 's world , accusing an athlete of using performance-enhancing drugs -- however baseless and lacking in evidence -- is toxic . '' The Filipino fighter , who has won world titles at five different weights , was slated to fight Mayweather on March 13 next year in a money-spinning bout in Las Vegas . But he was infuriated by the insistence of Mayweather 's camp that he undergo Olympic-style pre-fight blood testing and the alleged implication that he had used illegal drugs . Pacquiao posted a Christmas day message on his personal Web site , saying he would take legal action and has now followed through on the threat . Top lawyer Daniel Petrocelli is representing him and outlined the substance of their case . `` Manny Pacquiao 's achievements come from God-given talent and an indefatigable work ethic -- not steroids , '' he told gathered reporters . `` He can not and will not allow others to deliberately misrepresent his years of hard work and tarnish his reputation . '' The lawsuit seeks damages in excess of $ 75,000 dollars and also cites interviews given in various publications that appeared to question the fairness of Pacquiao 's pre-fight preparation . Mayweather 's connections attempted to diffuse the situation in a statement issued earlier this weak on the Golden Boy Promotions Web site . `` Let it be very clear that nobody from Team Mayweather or Golden Boy Promotions is accusing Pacquiao of anything , '' it read . `` But the reality seems to be that for whatever reason Pacquiao does not want to participate in random blood testing , which has already been deemed a harmless procedure that many current athletes are subjected to prior to and during competition , '' it added . Many viewed the war of words between the respective camps as a pre-fight war ploy to boost interest , but the row over dope testing may well have derailed one of the richest fights in boxing history , with huge pay-per-view revenues forecasted . The Los Angeles Times reported on Wednesday that Pacquiao 's promoter Bob Arum was pessimistic about a March showdown between the two fighters . `` This is only my opinion , but I do n't see the fight happening now , '' he was quoted . Positions are hardening ... Manny 's fit to be tied . He 's very angry . '' Arum was also reported to have opened negotiations with World Boxing Association super welterweight champion Yuri Foreman to fight Pacquiao .
Manny Pacquiao files lawsuit in Las Vegas against Floyd Mayweather Jr. and his connections . Filipino boxing hero is angered by alleged claims that he used performance-enhancing drugs . Mayweather 's camp want both boxers to submit to Olympic-style dope testing in build-up to proposed fight . Pacquiao is angered by this insistence and warned on Christmas Day that he would go legal .