Your words make you seem quite young if your recall goes only as far back as Sampras and Agassi. You have not seen the likes of Connors, Borg and McEnroe, Lendl play, let alone even heard of players such as Bill Tilden, Pancho Gonzalez, Ken Rosewall, John Newcombe, Rod Laver, Roy Emerson, etc. Please look up the page on Rod Laver on wikipedia as also the section there on Laver's place amongst the all-time great tennis players; it will offer you a deeper appreciation of many players over the decades as also where Sampras and Federer are said to stand amongst them. It is quite possible, though, that you will cling on to Federer and Nadal as they are the only two you really know something about !!! It is not to deny Federer and Nadal's pre-eminence in the current time but for all-time greats you have to look at a much-longer time span than just the last decade or so.
