Novak Djokovic has been No. 1 in the ATP world rankings since Nov. 5, 2012. That's a run of 48 consecutive weeks (he's been No. 1 for a total of 101).

That run could end this week at the China Open in Beijing.

To stay atop the tennis world, Djokovic needs to win ... and he has to hope Nadal doesn't reach the final.

That might be asking a lot, considering Nadal has played in 13 tournaments this year and reached the final in 12 of them (he lost in the first round at Wimbledon). He is 61-3 overall with 10 titles.

"(It) will be very tough to become No. 1," Nadal said. "But if I am still playing the same way that I have the past couple of months, I hope to have my chance here or in the next few weeks.

"This year, even if I started a little bit later [in early February], I am completing a great season. I'm playing one of the best seasons of my career. That's why I'm in a good position in the Rankings and I had great successes in the important tournaments."

Djokovic, the 2011-12 year-end No. 1, wants to stay at the top.

"As long as there is a chance, I will fight for that top spot," he said. "But, again, with no doubt (Nadal) has had the best results this year. This year, he's been the best player in the world. I have been having ups and downs throughout this year. But still it was quite a good season for me. But it's not over."