Hulk Hogan's a legend who put wrestling on the map, but he ain't the greatest of all-time ... at least not according to WWE HOF'er Stone Cold Steve Austin.
The guy who wears that crown ... is none other than the Nature Boy, Ric Flair.
"He's the absolute greatest of all-time to ever lace up a pair of boots, and the greatest world champ of all time."
TMZ Sports talked to Stone Cold -- hours before WWE's Monday Night Raw Reunion (featuring Hulk, Ric and other pro wrestling legends) -- about his relationship with the 70-year-old icon.