'Sugar' Shane Mosley -- Get Me to Miami, Stat! Don King's Trying to Screw Me

"Sugar" Shane Mosley is power-dialing his travel agent right now to get on a flight to Miami ... in a last ditch effort to take down Don King in court -- and save his comeback fight.

TMZ Sports has learned Mosley got bad news from Wednesday's hearing in a Miami federal court -- where King is trying to shut down Mosley's Aug. 29 bout with Ricardo Mayorga. Shane is not only the main event, he's also promoting the fight -- but King claims Mayorga is still one of his fighters.

Our Mosley sources say after today's hearing … Shane is looking to jump on a red-eye in order to make it to Miami in time to get in front of the judge Thursday.

Should be interesting -- we're told the hirsute one will also be in court.