"If you want to get some legitimacy in the game, fight somebody with a name!"
That's former boxing superstar Antonio Tarver -- who famously defeated Roy Jones Jr. TWICE -- calling out Jake Paul for a sanctioned fight!
"I want to fight him, because I want to show him there are levels to this," Tarver tells TMZ Sports.
FYI, Tarver is 52 years old and hasn't fought in 5 years. Jake is 23 and coming off a highlight-reel knockout of Nate Robinson.
Antonio -- who famously starred as Mason "The Line" Dixon in "Rocky Balboa" -- says he was VERY impressed with Jake's performance and thinks a fight with Paul would be super entertaining and a lot closer than most people think.
"When you look at Jake Paul's ability, you would be crazy not to believe he's much better than his 2-0 record indicates," Tarver says.
Paul has been calling for fights with guys like Conor McGregor and Dillon Danis ... but Tarver says if he's serious about a career in boxing, he needs to fight a BOXER.
"Get in the game and make a move, make a serious move. I can baptize you to the top level."