Antonio Brown 'Extremely Serious' About Buying Denver Broncos W/ Kanye West

Antonio Brown says he and Kanye West are dead serious about their efforts to buy the Denver Broncos ... telling TMZ Sports they're working hard to get a real deal done.

Brown and Ye have become best buds ever since the NFL star was booted from the Buccaneers in January -- and in their newfound bromance, Ye named Brown the president of one of his biggest ventures, Donda Sports.

And, as one of Brown's first actions in the exec role, he said back in February he wanted to purchase the Broncos.

When we got the free agent receiver out in Los Angeles just days ago, he told us the goal is still on their minds, and it's a legitimate one, explaining he and Ye are "extremely serious" about making it all happen.

"Tell Roger [Goodell] to call me," Brown said. "We're working on it ... We're working towards getting it done."

The Broncos just recently went up for sale, and many believe the price tag to ultimately land the team could be around $4 BILLION. If somehow the two are able to get that change together, a sale to Ye and Brown would also have to be approved by the rest of the owners in the league.

In the meantime, while they work on getting a deal in Denver done, Brown and Ye have more immediate goals of rockin' the Rolling Loud music festival in Miami in July.