'I am not disappointed with the whole season so far but...'

Novak Djokovic's season has fallen short of the expectations he had at the end of last year although he remains confident he is still on course to reach the very top of the game.

The Serbian left Shanghai after winning the season-ending Masters Cup last November as world number three with the Australian Open title under his belt, professing his belief that he might even claim the number one spot in 2009.

The 22-year-old returned to China this week as world number four with just the titles from Dubai and Belgrade to show for seven appearances in finals this year.

"If I expected to do something bigger than I did this year then yes, probably, but I am not disappointed with the whole season so far," he told reporters after first round win over Romanian Victor Hanescu at the China Open on Monday.

"I had the best clay court season ever up to the French Open. So I try to always look on the bright side.

"I did make some changes this year... that were maybe keeping my mind off court a little bit but I'm confident I can play very well and be a candidate for a grand slam in coming years."

Djokovic, second seed behind Rafa Nadal in Beijing, thinks his lack of progress, on the rankings front at least, might be down to the improvement of rivals like world number three Andy Murray and US Open champion Juan Martin del Potro.

"Even though I played quite well throughout this year I dropped a place in the rankings. That proves how well the other players are doing," Djokovic said.

"It's a matter of consistency, especially these days when you have Murray, Nadal, (Roger) Federer and Del Potro as your main opponents and rivals for the top spots in the world.

"They are playing so well and so consistent and in order to keep up you have to do the same and even better."

Djokovic, who lost to Federer the US Open semi-finals last month, hopes he has another weapon to help him reach the top after starting to work with twice grand slam finalist Todd Martin.

"He was an all-round player at the highest level of tennis for many years so he knows what its like to play in big matches, and it's certainly going to help me out," said Djokovic.