"First of all, in any sport where you can measure distance, height speed and all of that, you see how athletes have changed their sport and made it better. I believe, with every generation, the sport has improved. Certainly, in the men's game, that has been the case. I think that I played Pete [Sampras] at his best, I played Roger [Federer] at his best.. I believe wholeheartedly that Roger and [Rafael] Nadal have pushed the game much further than myself or Pete ever did. Their options on the tennis court are considerably more than ours."