Lamar Odom is stepping back in the boxing ring, but this time he ain't scrapping with a childhood pop star ... L.O. is fighting former heavyweight champ, Riddick Bowe!!
Celebrity Boxing founder Damon Feldman tells TMZ Sports they've inked a deal pitting the 6'10", 41-year-old former NBA All-Star against the retired 53-year-old pugilist.
The fight is set to go down October 2 on Fite.TV ... from the James L. Knight arena in Miami.
The legendary, 43-1-1 former undisputed heavyweight champ -- who once beat Evander Holyfield -- hasn't fought in over a decade .