I favour "The Argentine Strong-Boy", putting up good show against Frazier twice and still standing and if fought Ali under 50s rules would have got through full 15 rounds, again a creditable result, sure proved his worth, hence my choice as Bonavena being the winner vs Corbett Though if Corbett got on his bike and sidestepped as he was well able to, Ringo could well have been punching clear air for 15 rounds. Corbett would have lost the verbal battle, as Bonavena was a rare breed having managed to out trash talk Ali prefight, few ever did that., though respect was shown by both post fight. Bonavena a damned tough hombre indeed, though not tough enough to stop a bullet to the chest ending his life all too early at age of 33
I guess that with fifteen rounds to last, Corbett would hang on and take the decision. He might get mauled and stopped though.
Indeed he was not hence why i mentioned it, but managing to out trash talk Ali takes a lot of doing, and of course Bonavena did it to Frazier and the like also. Yes Mr Corbett was well able in this area too.
Corbett would probably make Ringo look silly with his speed and footwork,the question would be can he keep out of trouble for 45 minutes? He managed it against Jeffries for over an hour so maybe he would?