Odell Beckham Channels Inner Underwear Model in IG Pic

Here's Odell Beckham grabbin' some balls off the field ... thirst trappin' with a selfie in his skivvies!!

The Cleveland Browns superstar posted a pic in his boxer briefs on Monday ... channeling his inner Calvin Klein model and grabbing his crotch.

"Here’s a pic of me and a world class lamp," OBJ joked ... adding, "When y’all first start talkin and she asks u to send a selfie but u got a lil creep in u"

FYI -- Odell is part of CK's fall underwear campaign ... along with other huge names like Naomi Campbell, Diplo and Bella Hadid.

Of course ... the dude's getting roasted by some trolls ... but also getting a lot of love from his admirers.

OBJ ain't the only Browns stud showing off his underwear ... remember Baker Mayfield's epic PSD photo shoot with a REAL tiger??

Hey ... if you got it!!