Surely you need to define the question, greatest at their peak? greatest in the PL? scored the more? best overall player? best player in relation to the world at the time etc you need to define the criteria to get some order in here.. I think the question for most is who was best over the longest period, "best" being relative to what you would expect from someone in their position, so an attacker would be rated on goals and assists, there's reasons for and against everything, I don't think this is as far or as close as some suggest, If Ronnie keeps this up for another 2 years though, I think they would become far between as Henry took a while to peak and had a lot of injury plagued seasons, there's another element there, availability, some will cite the fact that "this player played less, so proportionality speaking...", when that's irrelevant, it assumes the player playing less would have been able to maintain a standard, or that if CR had been rested more, he could have produced better per game stats..