Throughout most of the 1990s, you could all but hand the Australian Open trophy to Andre Agassi, and during most of the 2000s, Roger Federer winning the title was a foregone conclusion. In 2008, however, the landscape of tennis changed. Gone are the days when only two or three men have realistic championship aspirations. A new era in which any number of players could conceivably make runs to Grand Slam titles is upon us. The first Grand Slam of 2009 is only two months away, so let’s take a look at the top contenders for the upcoming Australian Open.

Rafael Nadal – Knee tendinitis forced Nadal to withdraw during his semifinal match against Nikolay Davydenko at the Masters Series Paris, and it has since forced him out of both the Masters Cup and Spain’s Davis Cup final against Argentina. When the world No. 1 was healthy in 2008, however, he won almost everything. The Spaniard captured his fourth French Open, first Wimbledon, and also added Olympic gold in singles. Nadal reached the Australian Open semifinals last year and the hard courts there are slower than those of the United States, so another impressive performance should be expected.

Roger Federer – The Swiss lost his No. 1 ranking to Nadal and his quest to regain it will get underway at the Aussie Open. Federer reached the semifinals last season before a loss to Novak Djokovic ended his three-year reign. Assuming Federer’s back is well-rested by January and he is completely healthy (unlike in 2008), he will have a great chance of taking back the title.

Andy Murray – There is nobody hotter on the ATP right now. Murray won consecutive Masters Series titles in Cincinnati and Madrid, reached the final of the U.S. Open, and is now in the semifinals of the Masters Cup. The Scot had to play eventual runner-up Jo-Wilfried Tsonga in the first round Down Under last year, but he will not let another first-round defeat take place. Anything less than a semifinal performance at the 2009 Aussie Open would be a major disappointment.

Novak Djokovic – The Serb went through a dismal slump after the U.S. Open, but he seems to be back on track at the Masters Cup, where he has already qualified for the semifinals. That should give him confidence heading into 2009, and returning to the site of his first Grand Slam victory will certainly offer additional inspiration. Djokovic will have a great chance of defending the title.

Other contenders include Tsonga, Andy Roddick, and Juan Martin Del Potro. As we saw last year in Australia, when Tsonga gets on a roll, he is almost impossible to stop. Roddick has never performed up to expectations Down Under, but his serve always gives him a chance in any hard-court tournament. Del Potro took the tennis world by storm this summer, winning four straight tournaments in between Wimbledon and the U.S. Open. A Tsonga-like run from the Argentine at the 2009 Australian Open would not be surprising.