Rafael Nadal, who ended his season with a loss to Novak Djokovic in the semifinals of the ATP World Tour Finals, says that the Serbian is clearly the best this year, but 2016 could be different.

“Novak for the moment is almost unbeatable. The only thing you can do is congratulate him,” Nadal said. “But things are like this today. You never know what's going on in the future. I have been in very good situations a couple of times, then I get some injuries, things change. Not everything is that easy. What Novak is doing is just amazing. But is obvious that it's true if somebody can do it, it's him, but it's not easy to stay at that high level four years in a row or five years in a row.”  
Head-to-head, Djokovic and Nadal are now 23-23—tied for the first time in their careers after Djokovic won their four meetings this year. Nadal won their first-ever meeting back in quarterfinals of the 2006 French Open when the Serbian retired after two sets. The Spaniard then kept the lead in their head-to-head rivalry for years until Djokovic finally caught him.  
“Obviously after 46 matches and 10 years of professional tennis, I managed to tie my head-to-head score with Nadal. It took a lot of time,” Djokovic said. “ I think I was a few levels under him at the beginning of my career when I started playing professional tennis. Nadal was alongside [Roger] Federer dominating the tour. I just couldn't really do much against him. But because we played so many times I had a chance to really shorten the gap, and now even the score.”