The top eight players in the world have gathered in London to compete in the ATP World Finals, which commenced on Sunday. This end of the year competition, aside from being a showcase for the best players on the planet and a spectator's delight as each match contains the highest level of competition, also has some tangible importance as Roger Federer vies to end the year ranked number one for the fifth time (Pete Sampras holds the record with six).

The only person with the ability to deny Federer of that honor is his longtime nemesis-in-residence and utter kryptonite, Rafael Nadal. But Nadal, who finished the 2008 campaign ranked number one, has not been the same player since injuring himself in the spring. And he still seems to be nowhere near his prime. This was evident today as the 23 year old Mallorcan was brushed aside in straight sets by Rafael Soderling, the man who pulled off the tennis upset of the decade when he beat Nadal at the French Open in May.

So vengeance was not the theme of the day for Rafa. Only questions. And the whispers that have been present all year regarding Nadal's fitness and future will only get louder unless he makes significant noise in this round robin event. He has not beaten a player ranked seventh or higher since May. The honorable and ultra-competitive Spaniard continues to state that he is gradually getting back into peak playing form and says he is generally encouraged with how he has progressed since his heartbreak at not being able to defend his Wimbledon title.

But the proof has been scant thus far. And what is perhaps most alarming is the apparent loss of foot speed. The electrified scampering around the rectangular court is a trademark of Nadal and has often been the difference in many a crucial match. However unscientific and anecdotal the evidence may be, his court coverage is clearly not as complete as it has been in recent years. Now, this may in part be due to his ever maturing game as he realizes that he cannot continue to be as aggressive in going after every ball in the interest of long term survival at the top of the sport. But whatever the case, the ridiculous winners at insane angles that he used to hit while on the run with apparent ease are not as numerous.

Speaking of being aggressive, his legions of fans and admirers in the press have urged Nadal to become more forceful and seize advantage of a point early on.

But so many forget that change is a most elusive trait for most humans and even rarer with athletes. It is not so easy to actualize a metamorphosis in the sporting arena. Many tend to forget that. Stubbornness is a powerful, some would say necessary, virtue to most athletes and artists.

"To thine own self be true" - perhaps Shakespeare's most oft quoted line. Though it has been taken out of context from its original meaning in the play (where it served as a warning of sorts from Polonius to his son Laertes to be careful of one's status and possessions), it is nonetheless instructive when discussing change - for anyone in any field. And it is not so simple a task for anyone, let alone Nadal to just change his game.

Our current president is faced with a similar conundrum. Many - from both sides of the political divide and for different reasons - have urged him to take a firmer outward stance on any number of issues. Yet Obama is what he is and he knows he was elected for having a bold vision but also being even-tempered and possessing a scrupulous makeup. But now it has become clear to his supporters and detractors that action must be taken and lines drawn. And it's now a foregone conclusion that nothing of substance will issue forth unless he does so.

Rafael Nadal faces such straits. Whether he knows it or not - and I'd bet his uncle and coach Toni Nadal is cognizant of such - Nadal must augment his game now or risk falling far behind. Whether it's bolstering his improving but still average serve, stepping in several feet closer on returns or rushing the net more frequently where he can showoff his vastly underrated volley acumen, Rafa's mission is nearing a state of urgency.

Nonetheless, in case anyone jumps the gun and prematurely starts to write an obituary on Nadal's brief yet illustrious career, perhaps it's best to remember this: Nadal has accomplished what Jimmy Connors, John McEnroe, Ivan Lendl, Boris Becker, Stefan Edberg and Andre Agassi couldn't do. That is, win a Grand Slam event five consecutive years. Only three men in the Open Era have surpassed that - Bjorn Borg, Pete Sampras and Roger Federer.