Here http://www.footandba...he-modern-era/?
Personally I think "Hardest" has got confused with "Dirtiest". I think we all know top players that were rock hard but weren't filthy players. And conversely really dirty players that weren't all that hard.
I'm not sure if it's ironic or not but of all the players cited here, sleekit and dirty as he was, the one adjudged to be the hardest was arguably the best ball player. .