Here's the deal ... D.C. loves Snoop. Loves all his music. So, you can imagine how crushing it was to hear someone you respect attack you the way Snoop did.

In case you missed it, Snoop said Jones is gonna "kick [his] mother f**king ass" when they square off in their long-awaited rematch.

So how did the light heavyweight champ feel about it? "It sucks sooooo bad!"

Cormier says he's confident things will change after the fight ... and says he's got another huge rap superstar in his corner.