"He's going to have a lot of time on his hands and he needs to put it to good use," Merriman tells TMZ Sports. "So, bring some of that aggression over here!"

Merriman currently helps run the Lights Out Xtreme Fighting league ... and he tells us he's straight-up ready to get the troubled Raiders linebacker a scrap in his cage.

And, why? The ex-Chargers superstar says it's pretty clear ... Burfict is a BAD man -- and he could be a seriously entertaining MMA fighter.

"I just talked to my partners right now," Merriman tells us. "We want to make Vontaze Burfict an offer to come and fight."

Of course, Burfict ain't exactly out of NFL options just yet ... he's still in the process of appealing the season-long suspension the league just handed down to him this week.

But, if the NFL does uphold its initial decision ... Merriman seems all-in on the idea of seeing him scrap in the LXF, telling us, "We got a place for you!"