If you're gonna sit front row at a Vince Neil concert ... you better know how to duck ... because he might try to PUNCH YOU IN THE FACE!!!!!
TMZ has obtained video of the Motley Crue singer taking a closed-fist, rage-fueled SWING at a front row concert-goer during a show in New Mexico over the weekend.
Why, you ask?? Neil had just started performing "Kickstart My Heart" when the fan did something that pissed him off. Vince stopped the song and started yelling at the guy to "get the f*ck outta here!"
When the guy started getting mouthy back at Neil, the singer reached back and tried to punch the dude in the kisser ... but the guy ducked ... and Neil totally whiffed.
Didn't faze Neil though -- security rushed in and escorted the trouble-maker out of the show ... and Vince got right back into the song like nothing ever happened.
No harm, no foul ... right?