Lenny Dykstra Violently Calls Out Aaron Carter, I'm Gonna Pick This MF'er Apart

"I'm gonna f***** take this mother f***** apart piece by piece, okay?"

That's 58-year-old, former MLB star Lenny Dykstra promising to beat the ever-living hell out of 33-year-old Aaron Carter ... in a Celebrity Boxing match this fall.

😲😲😲😲😲

Here's the deal ... Carter inked a deal to fight October 2 in Miami -- but doesn't yet have an opponent. He even made a video, looking for a dance partner.

Welp, seems he might've found one in the 3x All-Star aka "Nails" ... who responded with a video message for AC.

"Lenny Dykstra here, nails. Guess what? I'm going back in the ring October 2nd in Miami with Aaron Carter. I'm gonna f****** take this mother f****** apart piece by piece, okay? October 2nd. In Miami. Don't miss it. Me and Aaron Carter. Mono e mono. Let's get it on, nails back in action."

We're told Celeb Boxing is trying currently trying to lock Dykstra in ... which would make the fight official.

Of course, Carter fought Lamar Odom in June ... and was knocked out in the 2nd round.

Can't knock Carter too much ... Lamar had a foot height advantage. Dykstra is much closer to Aaron's size.