Bobby Lashley Wants to Fight Brock Lesnar

Bobby Lashley wants a piece of Brock Lesnar -- not as a pro wrestler -- he wants a REAL DEAL MMA FIGHT ... and tells TMZ Sports it's a fight he knows he can win.

Lashley got famous as a pro wrestler ... racking up titles in WWE and TNA -- but now he's killing it in MMA, with a 5-0 record in Bellator's heavyweight division.

The 40-year-old brawler says he knows the biggest fight of his life would be against Brock -- and now he wants to make it happen.

Lesnar has hinted that he ain't done fighting yet ... so ... superfight???