I'm not talking about "for his era" type of argument, like Agassi hit way harder than the rest of the tour when he arrived than Del Potro does now in comparison to HIS peers. I'm talking about adding up the miles per hour of a player's serve, forehand, and backhand, and averaging it out. And I'm talking about how hard they hit consistently, on a point by point, game by game basis, and not about being able to crank one every so often. Like Felipe Lopez, yeah, he can rip a forehand sometimes, and he's got a potent serve, but his slice backhand.... Or Roddick, for a while, I thought he had the biggest serve + forehand combination in the history of tennis, and his serve still takes the prize for MPH, but his forehand is loopier than before and his backhand was never a screamer. But Del Potro consistently hits the cover off the ball on all three strokes. In the finals of the US Open, not sure if I've ever seen somebody hit so hard for so long. That might have been the biggest display of power tennis I've ever seen. And Fed is no slouch either in the History of Power category. But Del Potro had an extra gear. I'm not saying power equals tennis greatness. Clearly, Fed is a better player, and I might still be inclined to say Andy Murray is still a better player than Del Potro as suggested in the title of another thread in this forum. So Del Potro. I think he might be the biggest hitter (and I explained what I mean by that) in the history of tennis. Thoughts?