Novak Djokovic said his sick father inspired him to victory over Roger Federer in the final of the ATP World Tour Finals on Monday.

Srdjan Djokovic was absent from his customary position courtside as he battles to recover from a blood disorder that struck suddenly last month.



Despite dealing with the pain of knowing his father was seriously ill, the world number one managed to produce some outstanding tennis as he defeated Federer 7-6 (8-6) 7-5.



The victory capped off another highly successful year for the Serb as he clinched his fifth Grand Slam title in Melbourne as well as winning three Masters tournaments and making the final of two other majors.



"Throughout the whole season I've had lots of success and had some disappointing losses at big events, in a couple major finals," he said.



"But, you know, all in all, it was a fantastic year, where I've had to face a lot of difficulties off the court as well.



"You know, especially coming into this tournament, having my father fighting his own fight for health gave me extra strength that I wanted to play for him in a way.



"That's one of the reasons I really gave it all every match, especially tonight. This was a title for him."



Federer, who was bidding for an unprecedented seventh World Tour title, was typically gracious in defeat, but did lament his struggles on serve as he was broken four times throughout the match.



"I think the quality was good. I shouldn't have been broken as often as I was broken today," he said.



"But then again, that obviously has something to do with Novak. Overall, I think it was a great match. Yeah, I think I played very well. It was extremely close today."