Most Relentless fighter in history

[New England]

rocky marciano
aaron pryor
joe frazier

henry armstrong might be the best. he was often too relentless for his opponents from 126 - 147 to finish the fight.

[IronDanHamza]

First person that came to my mind was Henry Armstrong.

You couldn't fight Henry Armstrong without getting into a fight with him. Keeping him off you is something almost everyone tried to do, but couldn't prevent.

His fight with Barney Ross, one of the finest and most skilled counter punchers of his time had no choice but to stand toe to toe with him mainly because of his relentless pressure.

[The Surgeon]

First person that came to my mind was Henry Armstrong.

You couldn't fight Henry Armstrong without getting into a fight with him. Keeping him off you is something almost everyone tried to do, but couldn't prevent.

His fight with Barney Ross, one of the finest and most skilled counter punchers of his time had no choice but to stand toe to toe with him mainly because of his relentless pressure.

Yeah i think Armstrong is about as Relentless a fighter as there ever was
Or will be for that matter, despite fights being fought over 12 rounds now!

[Debopam Roy]

Frazier, Marciano, Dempsey, Jeffries, Johnson, Louis, Ali, Holyfield!

Hell of a big list, eh?

[Anthony342]

Hagler
Chavez
Marciano
Frazier
Pryor

Also Tyson in his prime, in earlier rounds or when he had someone hurt, maybe also Holyfield, although he might be considered more of a warrior rather than a swarmer, but still seemed relentless in throwing punches. In terms of relentless volume punching, someone like SRL at times or Paul Williams.

Henry Armstrong

[Khmelnytsky]

Ketchel
Papke
Greb
Armstrong
Duran especially at LW
Fenech
Chang
Jirov

[rightsideup]

a lightweight Roberto Duran kept coming and carried ko power into the late rounds.

[Khmelnytsky]

Basilio
Harada
Moon
Qawi
Walker

[raskat]

I am surprised so many mentioned Hagler, I disagree a little bit. I don't think Hagler was a relentless stalker. He also moved backwards in quite a few rounds; he keeps coming, yes, but not like guys like Pryor or Fenech.

[The Surgeon]

Sometimes i think that people think of Hagler purely as the fighter who tore into Tommy Hearns like a man possesed but in fact that wasn't his usual style