Mayweather-Berto has turned into full-on STAR WARS -- and Andre Berto is armed and ready to do battle after Sylvester Stallone took a serious pot shot at him.
We got Berto as he and Floyd Mayweather Jr. were leaving the news conference for their fight -- and we had to tell him about Stallone's jab. If you missed it, Rocky told us the only way Berto could win the fight is if Mayweather has a heart attack in the ring.
Berto tells us he WAS a fan of Stallone, but since he's "talking crazy" ... he's ready and willing to jump to another famous actor/boxer's corner.
He also hints Matt McConaughey, Chris Brown and some other celebs might be showing him some love in Vegas on Sept. 12.
In other words ... I got yer Bieber right here, Floyd.