John McEnroe called the Rafael Nadal-Roger Federer 2008 Men's Wimbledon Final the greatest tennis match ever.
It is the type of sporting that can give a sport a boost in popularity.
However, given that both players are not American, this is very unlikely to happen in the US.
It is no coincidence that the the '70s tennis boom in the US was at a time of many US stars—Arthur Ashe, Jimmy Connors, John McEnroe, Billy Jean King, and Chris Evert.
Golf is more popular than ever in the US right now. But, would it be if Tiger Woods was not from the US? At the very least, it is safe to say that golf would not be as popular right now in the US if Tiger was not born and raised here.
America likes excellence and winners; however, they care a lot more about the great US athletes than the great international athletes. Not that there is anything wrong with that or that it is difficult to understand why, just that this fact appears to be quite prevalent in US sports.
Great rivalries always increase interest in any sport, however, to have any big factor on a sport's popularity in the US, at least one of the athletes has to be an American (e.g. Borg-McEnroe). While Nadal-Federer may continue to be a great rivalry, it will have little impact on the popularity of tennis in the US. While the Williams sisters dominated Wimbledon last year, but do not really have a rivalry with each other.
Although, admittedly chess is not really a sport, the Bobby Fischer-Boris Spassky chess match and rivalry caused a chess boom in the US in the early '70s. However, after Fischer won and never defended his title, chess popularity in the US plummeted and has never fully recovered because Fischer was the last US World Chess Champion.
Hockey's popularity would have got more of a boost if Sydney Crosby was born and raised in the US. If Freddy Adu ever becomes the best soccer player in the world, is there any doubt that despite its lack of scoring (see last week's article on soccer's popularity in the US), that soccer would get at least a small boost in popularity in the US? Or if the US Men's Soccer team finally wins a World Cup?
American football, baseball, and basketball are the three most popular sports in the US and they are all still dominated by mostly US stars. Baseball and basketball, of course, have a decent percentage of foreign stars, but there is still plenty of US stars to keep its fans happy.
Hockey's lack of popularity has always been affected by the fact that it has few US stars and no US superstars. Boxing's lack of popularity right now is partly attributable to the lack of a current great US heavyweight—traditionally boxing's biggest star.
Yes, America loves a winner—especially if he or she is an American.