Lineage wise: there are four candidates:
Marvin Hart holds a victory over Jack Johnson, so he escapes the wooden spoon
Leon Spinks beat an aged Muhammad Ali, and in the early 80s at least showed glimpses, that he might of been a decent fighter, if he could of been bothered.
Primo Carnera is a bigcandidate, but it is very hard to judge what was and was not on the level. His victory over Sharkey saves him because....
Shannon Briggs has to be the worse IMO. Damn lucky to beat a 47 year old Foreman, beaten in five by Lennox in his first defence, he had a ton of potential pre Wilson, and still 10+ years later we are still staying he may have potential.
Alphabet crap wise: Johnny Nelson (twice), Adilson Rodrigues, Jimmy Thunder, Iran Barkley, Lawrence Carter, Joe Hipp and Audley all scream out as contenders, but to my mind a man who loses his title to Harrison in four rounds must be the worse... so I give you the Dutch Sonny Liston; Richel Hersisia!
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