At the beginning of 2008, Novak Djokovic got his season off to the perfect start. He defeated champion Roger Federer en route to his maiden Grand Slam victory at the Australian Open and the whole world was buzzing with Novak's play - and his tantrums!

Many still argue that he was only able to romp home with that title in Melbourne because Federer was suffering with glandular fever during the tournament, which he revealed in the month of March.

Defeating Federer catapulted Djokovic from wannabe to serious threat. The two Master Series titles - Indiana Wells and Rome - that he went on to claim before the French Open only substantiated views that he could be the No.1 player in the world by the end of the year.

Rafael Nadal came close to losing his No.2 ranking to Djokovic and he had to defeat him at Hamburg and Paris to keep the Serb behind him. This sudden urgency by Djokovic to tilt the tables at the top has ignited fire to Rafa, which has forced him to up his game. The result? Thrashing Federer at the French Open final, taking out Djokovic at the Stella Artois final, then and edging a thriller with Federer again in the Wimbledon final.

This has put Rafa in the limelight this year. But the clay and grass court season is over for good and Federer fans are now expecting normal service to be resumed on the hard courts of the US. Nadal shouldn't be a huge contender on the plastic surface, and that leaves Djokovic to be the only person who can challenge Federer between now and the end of the season.

Djokovic was knocked out in the second round at Wimbledon by a Russian marauder and no one has talked much about him since then. But that may prove to help Djokovic concentrate more on his game rather than taking a dig at top players. His racket should do the talking. Next up is the Rogers Cup, an event he won last year.

It's time for business for both Federer and Djokovic, while Rafa is the underdog in the second half of the season. Should the Spaniard make any inroads into the hard court season as he did on the grass, that should send shivers down the spine of the hard court specialists.

Rafa's knees have become the talking point more than his game after Wimbledon and any straight putdown on Rafa's game on the hard court should make people eat their words. Federer was hurt with his loss to Rafa at Wimbledon. Djokovic, on the other hand, had a good break after his second round loss, enjoying a skiing holiday in Europe.

While the first half of the season put Rafa in the limelight, it will be very interesting to see who will prevail in the second half and have the coveted No.1 ranking by the year end. Can Djokovic rise from the ashes and attain the glory the he acquired after the Australian Open? If he doesn't, cold water will be poured on him in a flash.

Really, it's Federer who should be the one getting ready to lift the No.1 trophy once again. But don't forget that it is the first time since 2002 he hasn't won a Grand Slam in a calendar year, so the pressure will really be on to reign in the US.