"I've done everything there is to do. The only guy that, to be honest, that even make sense right now is Wonderboy, 'cause he needs an opponent," 36-year-old Usman told TMZ Sports on Tuesday.
"Wonderboy's been around for so long, and he's just that name to where it's always a good fight."
40-year-old Thompson, a mainstay at the top of the 170 lb. division for years, has one of the most unique styles in all MMA (Kempo) ... and that's a challenge that excites Usman.
"His style is very, very difficult to fight. He's just one of those names, he's in my era, that I never really got to fight."
Of course, Wonderboy was supposed to fight Michel Pereira at UFC 291 on Saturday ... but the fight was scrapped after the Brazilian fighter missed weight, tipping the scale at 173 lbs.
Some fans and others around the sport have criticized Wonderboy for not fighting, despite the fact he cut and made weight, and Pereira didn't. Kamaru says those people are full of crap.
"I know everyone is crucifying [Wonderboy] for not taking that fight. But why? I don't understand that. Why?" Usman asked.
"People are like, 'He's a bitch.' 'He's scared.' 'He didn't want to take the fight.' Why? We signed on a contract, and [Pereira] said he was going to make this weight. He decided not to make this weight, and [Thompson] told him, 'Ok, I need you to go back and make this weight.' And if he's not going to try, why is that [Wonderboy's] fault? No, absolutely not [his] fault. People need to stop that."
"Wonderboy did his job. He came in there, he made weight, he trained for the fight. What more could you ask of him?"
There's much more ... we also talked to the future UFC Hall of Famer about his close friend and gym-mate Justin Gaethje's incredible KO win over Dustin Poirier at UFC 291, with the BMF belt on the line.
Kamaru talks about why the win was so important for his squad/coaches.