If Novak Djokovic is to dislodge Roger Federer from the top of men’s tennis, he clearly still has a long way to go after his disappointing straight sets defeat to unpredictable Russian Marat Safin at Wimbledon this week.

At just 21 years of age, Djokovic is seen by many experts in the game as being the natural successor to Federer, comfortable on all surfaces and with the ability to dominate when the Swiss star is injured or decides to call it a day. Admittedly, he does have the potential to be a No.1. He is already No.3 in the world behind Federer and Rafael Nadal and has been one of the most consistent players on the tour over the last 18 months.

Before his second-round defeat at Wimbledon this week, Djokovic had reached five consecutive semi-finals from the French Open in 2007, losing to Federer in last year’s US Open final, before defeating him en route to winning the Australian Open this year. He also reached the semi-finals of four of the five Masters events in 2008, going on to win in Indian Wells and Rome - the kind of season that Andy Murray can only dream of.

Djokovic’s Wimbledon blemish, however, means his chances of breaking the stranglehold at the top of men’s tennis will have to wait a little longer. They will only improve should Federer go on to lose his title at Wimbledon and also drop ranking points during the US Open Series from July - something that is not likely to happen easily.

There is a chance that Djokovic could dislodge Nadal from his position at world No.2. Nadal does not win hard court tournaments frequently enough to challenge Federer in the final half of the year, his last hard court title coming in at Indian Wells against Djokovic in March 2007. Djokovic’s game is better suited to the surface and if the Serb improves on his two hard court tournament wins last year, coupled with Nadal failing to better himself from last season, Djokovic could finish the season as the world No.2.

With Federer seemingly unshakeable on the grass of Wimbledon, his confidence should pick up ahead of the hard court season, and I fully expect Federer and Djokovic to dominate along with Andy Roddick on the surface. Nadal has only won tournaments in one year after the clay season ends in July - way back in 2005 where he won at the Canada Masters, China Open and Madrid Masters, although he did reach the final of the Paris Masters in November 2007, comprehensively losing in straight sets to David Nalbandian.