Problem with top tens are akin to being asked "What's your favourite song/movie/book/food/colour?" It's all subjective to that singular moment that the person being asked is in. Sometimes I wanna see a brutal decimation of an opponent, sometimes I love seeing the expert marksman at work and as such my top punchers will vary from day to day.

That being said I believe to this day Bob Fitzsimmons is the hardest god damn puncher in boxing that ever rose to prominence.