Jon Jones has NEVER been beaten (no, the DQ doesn't count) ... but Chris Weidman says he's gonna be the guy to hand Bones his first real "L" in the UFC Octagon!!!
Weidman -- the former middleweight (185lb.) champ who recently jumped to light heavyweight (205lbs.) -- has been Twitter beefin' with Jon ... and both guys seem down to a scrap.
TMZ Sports talked to Chris at LAX earlier this week ... and the UFC star had a short, but ominous message for Jones.
"See you soon, Jon.