Jamie Foxx -- SINGING NAT'L ANTHEM ... At Mayweather vs. Pacquiao

Jamie Foxx SINGING NAT'L ANTHEM

EXCLUSIVE

0427-floyd-mayweather-manny-pacquiao-jamie-fox-getty-01Another HUUUGE boxing role for Jamie Foxx -- 'cause he's just been tapped to sing the national anthem at the Mayweather vs. Pacquiao fight! 

Our sources confirm ... Foxx -- who's starring as Mike Tyson in an upcoming biopic -- was recently approached about belting out the "Star-Spangled Banner" ... and jumped at the chance! 

Foxx is a MAJOR boxing fan -- and famously starred as Muhammad Ali's right-hand man Drew Bundini Brown in "Ali."

This isn't the first time Foxx will be singing before a fight -- he belted out "America the Beautiful" before the Pacquiao vs. Mosley fight back in 2011 ... and CRUSHED IT!!!!

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