Jermain Taylor comes to mind for me. Jermain was 27 when he defeated Hopkins and captured the Middleweight championship. Hopkins was on top of the world back then, he hadn't lost since 1993 to Roy Jones, 12 year reign. When Jermain dethroned Hopkins I thought he had lots of talent and imo was on his way to ruling the middleweight division for quite some time. That is until he met with Pavlik, and I feel like his whole world got turned upside down. In that first fight he was beating Pavlik even dropped him early on. However, after getting knocked out, he didn't seem like the same fighter, I also thought he should've beat Froch and Abraham, Jermain definitely had superior skill. After that he took a hiatus, fought sporadically, and now shot his cousin, pulled his gun out at a parade, and apparently beat up someone up. His defense is mental problems, I think a prime example of a person who couldn't keep it together in and out of the ring.
Andrew Golota also gets an honorable mention.
Andrew Golota also gets an honorable mention.
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