UFC's Roy Nelson — Van Damme Coulda Fought UFC … Dude's Legit (VIDEO)

Jean-Claude Van Damme doesn’t just talk the talk when it comes to MMA fighting — he’s a REAL athlete who coulda competed in the UFC back in his prime … so says Roy “Big Country” Nelson

Roy isn’t just an accomplished UFC fighter in his own right — but spent some quality time with JCVD on the set of the upcoming “Kickboxer: Vengeance” flick.

And with Van Damme recently lecturing UFC fighters about how weak their leg strikes have become — we had to ask Roy if he thinks JC could back up his tough talk.

For the record, Van Damme is an accomplished martial artist — who won several fights as a teenager before becoming an action star.

There’s more … we also asked Roy how he’d fare in a showdown with Hafthor Bjornsson — the MASSIVE guy who plays The Mountain on “Game of Thrones.”

The 400-pound Bjornsson famously had a sparring session against Conor McGregor — but Nelson says he’d get CRUSHED against someone his own size.

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