Back on May 3, a short time after the Floyd Mayweather/Marcos Maidana fight at the MGM Grand in Las Vegas ended, Lil Wayne nearly got into an all-out brawl with Maidana's trainer Robert Garcia. And now, we know exactly why it happened, thanks to the video above.

As you can see in the clip, which was just obtained by TMZ Sports, Maidana's entourage was making its way back to the locker room that night after the match. And even though Maidana had lost, they were still singing and chanting and carrying on. So it appears as though Lil Wayne said something along the lines of "What y'all celebrating for?" to them, which prompted someone from Maidana's camp to throw a water bottle at Wayne. And from there, it was on with all hell breaking loose and Wayne trying to attack Garcia and others associated with Maidana.

You can check out the crazy scene in the video. All this over a water bottle?

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[via TMZ Sports]