Madrid, Nov 19 (IANS): Injured World No. 3 Rafael Nadal said Wednesday that it is his goal to be fully fit for the 2015 Australian Open tennis tournament and competitive enough to challenge for a 15th Grand Slam title.

Nadal missed the Association of Tennis Professionals (ATP) World Tour Finals in London after undergoing surgery to remove his appendix.

World No. 1 Novak Djokovic won the prestigious event to become the first player to win three straight season finale titles since Ivan Lendl won from 1985-87 when World No. 2 Roger Federer withdrew from the final due to a back injury.

The 28-year-old Nadal has also battled knee, wrist and back problems, with doctors confirming his rehabilitation included stem cell treatment.

"I have a month before Australia to get to my best level," he was quoted as saying by the BBC Wednesday.

"I hope to be healthy enough to work as much as I need and want, and if that happens I really feel confident I can come back strong."

Nadal won the the French Open title in June for the ninth time in 10 years. He will begin his comeback in an exhibition event in Abu Dhabi Jan 1 and then plans to play in the Jan 3-10 Qatar Open, where he is the defending champion.

The Australian Open begins Jan 19.