UFC's Marvin Vettori Baiting Chris Weidman, 'You're Gonna Be My New Girlfriend'

NEW FEUD ALERT!

Here's UFC middleweight Martin Vettori trying to trash-talk his way into a fight with Chris Weidman ... and guess what, Chris responded!

26-year-old Vettori -- who's on a 3-fight win streak -- is trying to get to that next level ... and feels a victory over Weidman would boost his stock and lead to bigger, more lucrative fights.

His plan is to try and embarrass Chris by calling him his GF -- hopefully, baiting the former champ into some back-and-forth that will build interest for a violent showdown.

And, guess what ... it's working!

After Vettori compared Weidman to a woman on social media and again during an interview with us (see above) ... Weidman fired back.

"Yo, Dork hop off my nuts and get a win over someone in the top 15 for 1st time in ur life," Weidman said.

"I have been beating guys in the top 15 for ten years straight. Relevant? There's a reason you are calling me out. I'll fight again when I'm ready too.. And btw you aren't that good."

So, what happens next? Marvin says he's followed up with UFC about putting a fight together ... but so far, nothing official.

He's even got a fight plan ready if Weidman accepts the challenge.

"I would grapple the sh*t out of him until he's dead tired and then just put him out."