I think it's an interesting question. Of course the big four are all clutch in their own right. I remember when Federer was at his peak, and I'd root against him...But he would always have the big serve in the big moment. I think the players who are successfully aggressive and take control of the match in the most important moments are the most clutch. Nadal as well.. in the big points.. when he was dominating.. you could always count on him to rip a forehand or have an insane passing shot in the crucial moments. Now we're talking about two of the greatest players ever here, but there are other clutch players on tour? Who do you think is the most clutch player?