Lamar Odom says he's not here to "play" boxing -- he's gunning to knock out Aaron Carter and embarrass the dude in front of his girlfriend.
The 41-year-old ex-NBA star is taking on the 33-year-old pop star in a 3-round exhibition Friday night at the Showboat Hotel and Casino in Atlantic City.
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Both guys have been working their asses off in the gym -- but Lamar tells TMZ Sports he could "really give a f**k" about Aaron's training program.
"I'm prepared," Lamar says .