Adrien Broner will have some major starpower in his corner when he takes on Mikey Garcia this weekend -- FLOYD MAYWEATHER

Broner and Floyd have a big bro, lil bro relationship with major ups and downs. But it seems they're on great terms at the moment ... with Floyd promising he'll be in the building to support AB on Saturday. 

"He called me the other day and said he was gonna be there," Broner tells TMZ Sports

Floyd's been training at his gym in Vegas -- but the Broner vs. Garcia fight is at the Barclay's Center in NY. 

No problem for Money May ... who can gas up one of his TWO private jets to make the trip. 

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