The rapper has teamed up with Triller co-owner Ryan Kavanaugh to launch a brand new pro boxing league called "The Fight Club" ... and we're told there's already a blockbuster event in the works!

TMZ Sports was talking with Kavanaugh about Snoop's wildly entertaining performance as a commentator at the Mike Tyson vs. Roy Jones Jr. fight ... when Ryan dropped the bombshell on us.

"This was the first event of a league that we have called 'The Fight Club,'" Kavanaugh said.

"It's a league owned by Proxima, which is the parent company to Triller and Snoop, and this was the first of many, many events."

Kavanaugh says Snoop is a co-owner of the league -- plus, he'll be doing fight commentary and helping book the fights and musical acts!

"This is gonna be big," Kavanaugh says ... "The whole idea is we want to change up the way that boxing is done."

The plan is for "The Fight Club" to put on both sanctioned fights and non-sanctioned fights ... basically, like the Mike Tyson card.

Kavanaugh says he's already got a MAJOR sanctioned fight in the works involving some huge stars.

"I can tell you that the main fight — I can't say it yet — but it’s gonna be something that everybody wants to see. If you thought [Tyson vs. Jones Jr.] is big, I think that this would be even larger from a worldwide-appetite perspective and something that people want to see."

Kavanaugh says the undercard will be stacked too -- they're currently looking at social media stars, actors, musicians, athletes and pro boxers to get in on the action.