Geneva - By his superhuman standards, 2008 was been an "off" year for Roger Federer, with only a fifth straight US Open title and the Olympic doubles gold medal added to his world-class collection of honours.

It was also the first season in half a decade that the 27-year-old Swiss failed to end the year on the top ranking spot after ceding the position to Rafael Nadal just prior to the Beijing Olympics.

While Federer's Grand Slam title count stalled on 13 as he attempts to pull level on all-time mark of 14 majors held by Pete Sampras, the calm Swiss is not in the least discouraged.

While some have doubted that a December 2007 case of glandular fever could have really put him off his game for up to half of the season, Federer says that the just concluded campaign was an anomaly due to his inability to train properly in the off-season.

And the man who has dominated the ATP like no other is hoping to start putting things right from January. But at his exalted level, only world number one means anything in the grand scheme.

"For me, honestly, ranking two, three, four, five, 25, it doesn't really matter a whole lot, it's number one," he said after losing for the first time before the semi-finals of a Masters Cup when he went out early in Shanghai.

New York aside, Federer won only three other events in 2008 (Estoril, Halle and Basel) and his 15 defeats were the most since 2003.

He recovered momentum even after losing a gripping Wimbledon final to Rafael Nadal: claiming the Beijing doubles gold with Davis Cup teammate Stan Wawrinka, beating Andy Murray for the New York title and winning his third straight home title in Basel.

Spain's Nadal faded at the end of his breakthrough year with a knee injury, forced out of the Paris Masters and an absentee from the Masters CuP and Davis Cup final, where his nation showed it was far from under-powered without him with a win over Argentina.

The 22-year-old, who won his fourth straight Roland Garros title and lifted the Olympic gold, ended with eight ATP titles and uncertainty about how much longer he can keep going hell-for-leather.

Serb Novak Djokovic started and finished the season well, winning his first Grand Slam trophy in Australia and claiming the Shanghai year-end crown.

That performance drew him to within 10 ranking points of of Federer, who said "I'll still be able to sleep" when informed of the news.

Britain's number four Murray announced his presence on the big stage with a US Open final and Masters honours in Cincinnati and Madrid. The Scot is taking his training seriously, heading off to his base in Miami for training and fitness work.

Off the court, players complained that the long season was leading to injury, with Andy Roddick the latest to go public with complaints from exhausted millionaire sportsmen.

ATP officials continued the search for a replacement to CEO Etienne de Villiers, set to quit at the end of the year partly over complaints on the injury issues.

The South African found himself without the support of Federer, Nadal and Djokovic, all of whom were elected to the Player Council in an unprecedented show of unity from the world top three.

The WTA continued to provide a merry-go-round of number one players, with Serb Jelena Jankovic ending the season on the top spot as the game of musical chairs stopped in November.

Maria Sharapova, a logical contender for the place after the shock May retirement of top-ranked Justine Henin at age 26, was unable to compete after Wimbledon as the Russian submitted to months of shoulder rehab.

Four-time Wimbledon winner Venus Williams won the WTA Championships in their debut in Doha, while sister Serena topped the money list on 3.59 million dollars and finished second on the year behind Jankovic.

Russian Dinara Safina won four titles from seven finals to emerge as a threat with her third-placed finish. French Open champion Ana Ivanovic was looking for consistency after failing to follow up on her Paris triumph, with only one small Austrian title to show.

The Williams sisters finished as the lone non-Eastern Europeans in the top 10, with Russian players alone occupying five pots. (dpa)