James Jeffries vs Anthony Joshua, both at their best. Year 1904, gloves, ring, rules of that year. 25 rounds. Joshua is taller and bigger, probably more muscular thanks to modern training. He is however a little slow, quite monotonous in style and especially with a vulnerable chin. Jeffries has extraordinary conditioning and stamina, can fight in different ways, has practiced wrestling. However, weak defense, tends more to wear down opponents gradually than to finish them immediately. Who wins and why?
We simply don't have footage showing Jeffries at his best. The footage we have of both fighters suggests that Jeffries gets turned into some kind of leather wall ornament after Joshua is through with him.