NEW YORK -- The highly anticipated mega fight between Manny Pacquiao and Floyd Mayweather is off, a Top Rank official told SI.com on Wednesday. Both sides are going their separate ways after an attempt to mediate the dispute over how the fighters would be drug tested failed earlier Wednesday.

Top Rank promoter Bob Arum says Pacquiao will likely face junior middleweight title holder Yuri Foreman on March 20 in Las Vegas.

Mayweather is expected to keep the March 13 date at the MGM Grand against an unnamed opponent. Golden Boy Promotions CEO Richard Schaefer, who was negotiating for Mayweather, could not immediately be reached for comment.

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