With Tennis Channel becoming more and more common in homes and tennis in general being televised more and more often, people are finally beginning to realize how vulnerable Roger Federer can be outside of slams. I've had countless conversations as to why Federer is more dominant in slams than in any other tournaments, and I keep hearing essentially, "Great players play their best when it matters most." While I don't necessarily disagree, I believe the real reason lies in Fed's level of fitness. In two-out-of-three set matches (non-slams), fitness, while obviously still being a huge component of the match, is not nearly as vital as it is in three-out-of-five set matches (slams). And Federer's level of fitness is astounding. The speed, grace, and endurance which he displays takes almost no toll on his body, and allows him to function at his fullest in fourth and fifth sets--sets when his opponent would love to stop and rest. However, in two-out-of-three set matches, Fed loses this fitness advantage. His opponents have simply not been on court long enough to tire them out. Do you really think Marcos Baghdatis would have beaten Fed at Indian Wells, for instance, had it been a five set match? I don't. Just a theory.