Federer not surprised to be still at top

MANY MAY BE SURPRISED BY Roger Federer's untroubled progress towards becoming the oldest US Open champion in almost half a century, but not Federer himself. 

The 34-year-old has glided into the semi-finals, where he will face Swiss compatriot Stan Wawrinka today. 

It will be his 10th New York semi-final as the five-time champion targets a record sixth US Open and 18th Grand Slam title. 

"For many years I have tried to look at the big picture to hopefully still be playing at a high level at this age,"

said Federer as reported by PTI, who would be the oldest winner of the US Open since Ken Rosewall in 1970. 

"So in some ways I am not surprised I am playing as well as I am." 

Federer has not won a major since his seventh Wimbledon title in 2012, but came into the US Open on the back of a seventh Cincinnati title, defeating world number one Novak Djokovic in the final. 

It was his 87th career title and pushed his on-court earnings to almost USD 94 million. 

His form in New York has been just as impressive, dropping serve just twice and not yet having lost a set. 

Despite his Grand Slam title drought -- the longest of his career -- Federer has not been afraid to keep innovating. 

In recent years, he has experimented with a larger racquet, brought in former world number one Stefan Edberg to work alongside long-time coach Severin Luthi and radically altered his playing schedule. 

The US Open is only his 13th tournament of the year. 

He has also invented a new tactic, the 'SABR' or 'Sneak Attack By Roger,' which is his chip-and-charge on an opponent's second serve. 

After his 87-minute quarter-final demolition of Richard Gasquet on Thursday, Federer also said he was sleeping more -- up to 10 hours a day -- to maintain his competitive level. 

"I think I have worked on my game moving forward, have been able to take the ball earlier,"

he said when asked to explain his longevity. 

"I think I'm volleying better than I have the last 10 years. It's all about keeping yourself in shape and staying injury-free. And motivated. 

"I've played so well over the last one-and-a-half years. I don't feel like I'm as old as I am. I still feel young." 

He has come close to adding to his 17 majors.