It's a good thing Jean-Claude Van Damme is flexible -- 'cause he put his entire foot in his mouth when he claimed UFC fighters don't know how to kick ... so says Chuck Liddell.
Liddell was flexin' out in Bev Hills Thursday when we asked what he thought about JCVD's criticisms -- when the movie legend told us the leg striking in the UFC is a "mess" because the fighters don't truly understand how to kick.
Chuck didn't take kindly to JCVD's opinion.
"He's ridiculous," Liddell said ... "He can say whatever he wants but he's never fought MMA."
"I kick pretty damn good."
In case you need video proof -- here's Chuck kicking the living crap out of people. Enjoy!