Gisele Bundchen -- Adriana Lima Would Kick Her Ass ... Says Pro Boxer

Sure, she put a hurtin' on a heavy bag in that new Under Armour ad -- but how would Gisele do in a real fight with fellow supermodel pugilist Adriana Lima?? She'd get her perfectly sculpted ass kicked.

At least according to actual boxing champ Peter "Kid Chocolate" Quillin.

By now you've seen the Gisele ad -- and it's impressive -- but she can't hold a candle to Lima ... who's been boxing for years and even trained with Manny Pacquaio.

"Seeing [Lima] hit the pads, I expect her to do better in the ring than Gisele," Quillin says ... noting her form, her power and her precision.

"Hitting the pads is different than hitting the bag ... it's harder. You have to have more direction with the pads. But you really never know what kind of fight someone has until they step in the ring."

But Quillin says he was definitely impressed with Gisele too ... especially when it came to her physique.