Novak Djokovic has insisted that he can achieve much more after finishing an impressive season by triumphing at the ATP World Tour Finals.
The world number one was unstoppable on the way to a 6-3 6-4 victory over Roger Federer in Sunday's final in London as he avenged the defeat he suffered to his rival in the group stage.
Djokovic's victory made it 11 titles in 2015 for the Serbian, who believes that he can remain at the top of the sport after winning three of the four Grand Slams.
"With the wins that I had this season and throughout my career, especially in the last five years, I put myself in a very good position, knowing that I made a lot of records and history," the 28-year-old told reporters.
"I'm convinced with this dedication to the sport, I can achieve more. How much, I don't know. I don't have a sense of urgency. I don't chase anything. I just try to be in the moment and see where it takes me."
Djokovic is the first player to win the ATP World Tour Finals four years in a row.
