Play video content EXCLUSIVE 4/9/19 TMZSports.com

UFC superstar Daniel Cormier says he wants to fight Brock Lesnar in the Octagon ASAP -- telling Dana White, "What are you waiting for?! Get this sh*t on the books!!!"

Of course, Brock got destroyed by Seth Rollins at WrestleMania Sunday -- a storyline many people think was written with the intention of freeing Lesnar up to go fight in the UFC again.

Which brings us to Cormier ... who had previously talked about retiring on his 40th birthday (which happened a couple of weeks ago) -- but now that Brock's in the picture, DC says he wants all the smoke.

"It’s the fight I want," Cormier tells TMZ Sports ... "I think everyone wants to fight Brock. We all want to fight Brock."

Cormier is the reigning UFC heavyweight champion -- and recently relinquished the light heavyweight championship.

He added, "It's the fight. That’s the fight that needs to happen. You know, he’s a former UFC champ, All-American in college. This guy's very, very deserving of a fight, and he’s gonna get it. Hopefully."

Dana White has previously told us he wants to make the fight happen -- but so far, nothing's official.

Cormier is trying to light a fire under White's ass to get the deal done.

"Dana get on the phone right now. If you haven’t called him yet, do it today!! What are you waiting for?! Get this sh*t on the books. Let’s get this on the books!!"

As for Brock, Cormier has a message for him too after his defeat at WrestleMania -- "Lick those wounds ... 'cause I got some brand new ones waiting for ya."

41-year-old Lesnar was a beast during his UFC heyday -- winning the heavyweight title in 2008 with a victory over Randy Couture.

But, he hasn't fought in the UFC since 2016 -- when he beat Mark Hunt in a fight that was later overturned after Brock flunked a drug test.

Will Lesnar take one last fight before riding off into the sunset??? Stay tuned.

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