First things first, 30-year-old Eblen, a 6'3" rising star in the middleweight division, has his hands full against 36-year-old Mousasi. The men are scheduled to fight at Bellator 282 on Friday for the 185-pound belt.

"I've been preparing for moments like this my entire life," Eblen told TMZ Sports, adding ... "I'm ready to show up and show out and have fun out there."

But, during our convo it became clear Eblen's goal isn't just to be Bellator champ -- as impressive a feat as that is -- 'cause he also wants to be a champ in Dana White's organization.

"I want to be a champion in Bellator. I want to stay in Bellator for a little bit longer, make money here. And eventually, if the cards line up correctly, I want to make the switch and I want to be the best middleweight in the world. And, you have to go do that in the UFC now."

FYI, being both UFC and Bellator champion -- regarded by most as the two top MMA promotions -- is rarified air. In fact, only Eddie Alvarez and Cris "Cyborg" Justino have been the top dog in both orgs.

Of course, just beating Mousasi is an incredibly tall task. He's 49-7 ... and has beaten Austin Vanderford, John Salter, Douglas Lima, and Lyoto Machida in his last four fights. GM has been fighting professionally since 2003.

Like Eblen, the current #1 ranked contender, Austin was undefeated at 11-0 before running into a Mousasi buzzsaw.

But, Johnny doesn't see himself losing that "0" Friday night.

"At the end of the day, everybody's human. So, you just gotta remind yourself that. Obviously, he's a legend of the sport. But, this is what I signed up to do. I want to fight people like Mousasi. I want to fight people who are the best in the world to solidify my name, my skillset, and who I am."