One of the greatest individual seasons in tennis history came to an end on Friday as Novak Djokovic was eliminated from the ATP World Tour Finals.
Djokovic's defeat by Janko Tipsarevic, coupled with Tomas Berdych's victory over David Ferrer, meant the 24-year-old Serb could not reach the semi-finals.
However, he ends the year in possession of the number one ranking, three of the four Grand Slam titles and a 70-6 win-loss record.
"I had an unbelievable year," said Djokovic. "Nothing can ruin that. I will always remember this year as the best of my life."
It ended his winning run at 43 matches dating back to Serbia's triumph in the 2010 Davis Cup final, and 41 for the year.
He was one victory short of equalling John McEnroe's best ever start to a year of 42 wins, and three behind Guillermo Vilas's all-time record run of 46 matches.
He beat 10-time Grand Slam champion Rafael Nadal in both finals and ended the campaign with 10 titles.
"He won everything a person can win," said fellow-Serb Tipsarevic. "He had the best season in the history of the sport."
After the US Open, Djokovic was troubled by back, abdominal and shoulder injuries, playing only eight matches between Flushing Meadows and the year-end championship at London's O2 Arena.
He scraped through his opening group match against Berdych before losing to Ferrer and Tipsarevic.
"My body says that it's overload," stated Djokovic. "It's been too much this year. Mentally I feel a little bit drained.
"I just don't have the freshness in my mind for the matches and I don't have the dynamics that I had in all 10 months of the year.
"But this is something to be expected after the year I had and now I just want to prepare well for 2012."
Djokovic will take some time off before beginning his preparations for 2012, with his first goal the Australian Open from 16-29 January.
"I will have a couple of weeks' rest and preparation," he added.
"I'm playing a couple of exhibition matches in Abu Dhabi and maybe some in Australia, then getting ready for Melbourne.
"I think I have more than enough time to get my old strength back and prepare well. So I'm sure that if I have as good preparation as I had last year, I'm confident I can do well in Australia."