Has there been a case where a (decent) fighter would lose to his trainer?

I can't think of any off the top of my head but I do remember watching the clip of when Roy Jones Jnr fought Glenn Kelly and Kelly had Jeff Fenech in his corner and they asked Emmanuel Steward if Fenech would have a game plan for Kelly to beat Jones and Emmanuel was honest and he said something like "I think that Jeff would have a better chance if he got in there himself"

 

Jonathon Banks trained Golovkin, Jack and a few other good fighters while being very recently retired from boxing. Being fairly young and considerably bigger he would have had a good shot at winning.

 

Probably plenty of examples in lower weights

 

Arturo Gatti wast rained by Micky Ward in his last fight-he won 2/3 in their high contact trilogy.

 

Any trainer of Campbell Hatton

 

Mark Breland and Wilder

 

Floyd Jr almost lost to Floyd Sr lmao

 

Buddy Mcgirt I have no doubt would've beaten Gatti

 

Rocky Balboa and Tommy Gunn came to the very top of my head.

 

Anne Wolfe would have made James Kirkland her *****.

 

Archie Moore trained Cassius Clay for a while. But Clay wouldn't listen. So Moore quit. That's why Archie signed to fight him in 1962. He wanted to teach the cocky young kid who wouldn't listen a lesson.

Didn't work out so well.

 

David Haye managed and oversaw the training and nutrition for Derek Chisora for three years.

Haye also wasted Chisora in five rounds and "glassed" Chisora in a previous post-fight altercation.

Haye totally owned Chisora.

 

He had no problems with Joe Gatti, that's for sure.