That's because I didn't watch the Hewitt match, or don't remember it. I just put down things I've seen that stuck in my mind to this day as pretty astonishing performances. I am sure there are plenty of matches I've missed, especially from the 90s. As for Nadal's 2008 RG, it's hard to pick a match from there (and I didn't want to pick more than one) because he was so dominant throughout the tournament. His level against Federer was also very high, of course, but at the same time, once Federer fell behind in the 3rd, it looked as if he just went through the motions a little bit. Djokovc is the only one who managed to put up some resistance. He won more games than Verdasco, Almagro and Federer combined.