29-year-old Walker -- the #10 ranked light heavyweight -- is taking on #12 ranked light Jamahal Hill at UFC Fight Night on Saturday ... a matchup Walker believes will catapult him back into title contention.

"Bro, if at any point that somebody said I don't wanna be champion, I'd quit. I'd get out. I'd stop. Because I believe 100% I'm a champion,"

Walked continued ... "I'm not doing this just to fight, just to have fun. I'm here for the money, I'm here for the success, for my career, for my family, for my future. I'm gonna be the champion. I believe that and nobody can tell me opposite."

Walker was once ranked near the very top of the division ... and it felt like a forgone conclusion he'd fight for the title. In fact, we had several conversations with Johnny about his future battle with Jon Jones -- a fight that never materialized.

Aside from Jon leaving the division, Walker hit a rough patch, losing to Corey Anderson in November 2019, before sustaining another L to Nikita Krylov in March 2020. JW then beat Ryan Spann in September 2020 ... before again losing, this time to Thiago Santos in October 2021.

Even before the mini skid ... Walker dealt with adversity, even in victory.

After his electric win over Misha Cirkunov at UFC 235 in March 2019, Walker dislocated his shoulder doing the worm on the Octagon canvas.

"I'm very excited with my career and everything then boom, I was down. I don't know what depression is actually, but I was a little bit down."

Johnny continued ... "I was no patience, I was a little bit sad, I almost lost myself a little bit, you know, and I was against my brother in Thailand, I shouldn't do that."

Despite the struggles, Walker says he's back, and ready to rock.