Jake Paul Challenged By Osundairo Bro, Ready To Fill In For Rahman Jr.

Hasim Rahman Jr. out -- Bola Osundairo in ... vs. Jake Paul?!

If one of the brothers who assisted Jussie Smollett in his hate crime hoax gets his way, that's exactly what'll happen ... 'cause Bola tells TMZ Sports he's ready to fight Saturday night at Madison Square Garden, as was originally scheduled.

“Do not cancel that fight Jake Paul. Fight me instead. I am ready to fight this Saturday," 28-year-old Bola said Monday afternoon.

The 2-0 pro fighter (who also had several amateur fights) tells us he's a superior fighter to both boxers Jake was set to scrap with August 6.

"I’m ready to fight. I’m better than Hasim Rahman Jr., or Tommy Fury. I’m actually ranked higher than Tommy Fury and he has 8 pro fights, and I have 2 pro fights. He’s ranked 340, I’m ranked 193."

23-year-old Fury -- Jake's original opponent -- dropped out of their fight after having Visa issues, leaving him unable to reach the U.S.

Of course, Bola was one of the two brothers who assisted Jussie in his hoax attack ... before cooperating with authorities. Smollett was ultimately convicted of 5 felonies.

In ways, the fight makes more sense than Rahman Jr., who's significantly bigger than Jake (Hasim previously fought weighing over 260 pounds). The fight fell apart over weight issues ... the 12-1 boxer wasn't going to be able to make 200 pounds, as was contractually obligated.

Bola is 6'1", 188 pounds ... virtually identical to the 6'1", 190 pounds that Paul weighs.

And, Osundairo says he's more well-known than Rahman Jr. ... so it'd be an even bigger draw.

"People know me. People know of me. I’m one of the Nigerian brothers involved in the Jussie case, the Jussie Smollett case. So it will sell, this fight will sell. People know me more than Hasim Rahman Jr. Nobody knows him outside of boxing."

Bola ended with a shot at Jake (and Jussie).