Federer can kick Nadal rivalry up to legendary status

	The best thing that could ever happen to world No. 1 Roger Federer (above) might be Rafael Nadal's recent domination of him. Bob Martin/SI
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For the sake of posterity, probably the best thing that ever happened to Muhammad Ali was getting beaten by Joe Frazier. Jack Nicklaus is all the more remembered that he moved to the top over the beloved Arnold Palmer. The records of Chris Evert and Martina Navratilova suffered that they had to deal with one another, but, in fact, they're both accorded all the more acclaim because they had to deal with one another.

You see, in a sense, any great champion almost requires a noble challenger to certify preeminence. Otherwise, in a way, how could we ever really know how big his heart, how high she could lift her game?

As fantastic as Tiger Woods is, his putative challengers -- the likes first of Duval, then Singh and Els and Goosen -- are themselves not the stuff of majesty. If Phil Mickelson really has moved up a notch, if his game (and his mind) have matured enough to raise him near Woods' level, then -- perhaps starting with the U.S. Open in a couple of weeks -- we can assess the depth and splendor of Woods in ways we never could when we were only blinded by his own brilliance.

It is tennis, though, where the potential for, quite possibly, the greatest men's rivalry in the sport's history suddenly looms. As the French Open moves into the second round Wednesday, all anybody anticipates is a final between Roger Federer and Rafael Nadal.

It is not just No. 1 vs. No. 2. It is Federer, the polite, lithe, rather restrained, right-handed Swiss vs. the animated Nadal -- the ebullient, muscular left-hander from Mallorca who favors a colorful bandanna round his head and clamdigger pants. Not only that, but Federer has come to be ordained as potentially the greatest tennis player ever. Simply that. Beautiful of stroke, wise with strategy, brave in battle.

So high did Federer's star rise as he won his seventh Grand Slam title this winter in Australia that even the xenophobic American sports public was forced to begin to accept him. ESPN dubbed Federer with the ultimate symbol of American sports knighthood: the opportunity to star in an ESPN house commercial. A foreigner acknowledged on ESPN? The bandwagon was now standing room only.

Only suddenly, on this glide path to easy immortality, there developed one little inconvenience. Namely: Federer keeps getting beaten by Nadal. Six times they've met. Five times the brash young Spaniard has won -- and not just on clay, Nadal's home surface. He's beaten Federer two out of the three times they've played on hard courts.

Nadal is obviously getting into Federer's otherwise uncluttered head. Two weeks ago, in their last meeting, in Rome, Federer screamed out, peeved, protesting that Nadal's uncle was illegally coaching him from the stands. Then the imperturbable Swiss master choked egregiously when he blew two match points.

Maybe the rather startling fact is that, yes, we're watching the greatest tennis player ever right now ... only maybe it's not Roger Federer.

Ah, but what if Federer beats Nadal and wins the French on clay, on his worst surface, defeating the defending champion? Then he's won four majors in a row and is halfway to a traditional Grand Slam, and he's achieved it by vanquishing the grand pretender on his own stage.

Of that is not just victory. It is that which turns mere champions into legends.

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