Rafael Nadal revealed he would have to double his efforts in regaining his best form to overcome Novak Djokovic next year, but the Spaniard admitted that as of now, the Serb is “almost undefeated.”

“The only thing you can do is congratulate him," Nadal said, Super Sport reported. "But... you never know what's going on in the future.”

Nadal is gradually recovering from the worst year of his career ever since his early exits at the Wimbledon and the US Open. The “King of Clay” showed glimpses of his elite form at the China Open and the Swiss Indoors, reaching the final rounds of both tournaments only to fall short against Djokovic and Roger Federer.

Nadal beat Andy Murray, David Ferrer, and Stan Wawrinka in the group stages of season-ending World Tour Finals in London. However, he was no match against Djokovic, losing in the semifinal round 6-3 6-3.

Nadal’s defeat at the hands of Djokovic may have ended another potential comeback of winning a tournament, but the 14-time Grand Slam winner said he would not be dishearten by the loss and would opt for some relentless training ahead of the Australian Open next year.

"My next step is just keep practising the way that I am doing,” Nadal added. “I know I need to keep improving things if I want to have chances against Novak next year.”

Meanwhile, Djokovic has completed an ATP World Tour Finals title four-peat after defeating Federer in the final round 6-3 6-4 on Sunday (Monday AEDT). The Serb, who improved to 18-1 at the Final Showdown amid his four straight title campaigns, won his 11th title of this year and completed one of the greatest seasons in his career.

Djokovic said he is “very proud” for his title achievements this season as he levelled his FedEx ATP Head2Head with Federer to 22-22, according to ATP World Tour’s official website.

Djokovic will join Federer, Nadal, and other top tennis players around the world in Asia’s International Premier Tennis League, which starts next month in Japan, Manila, New Dheli, Dubai and Singapore.

Contact the writer at feedback@ibtimes.com.au, or let us know what you think below.

RELATED STORIES