Roger Federer already has it all.

The Swiss master has nothing left to prove and hardly anything to lose.

In casino parlance, he is now playing with the house's money.

It has been that way for more than a year after he won the French Open for the first time last season then broke Pete Sampras's record of Grand Slam men's singles titles.

Inevitable questions about his motivation arose when he lost last year's US Open final to Argentina's Juan Martin Del Potro but he answered those in emphatic fashion when he won this year's Australian Open.

Photographs: Reuters

By his own standards, the rest of this year has been a flop, he has failed to add to his tally of 16 grand slam titles and lost his grip on the number one ranking.

He was beaten in the quarter-finals of the French Open, ending his sequence of 23 consecutive Grand Slam semi-final appearances.

Then, the unthinkable happened, he lost in the quarter-finals at Wimbledon, marking the first time he had failed to reach the final at the All-England club since 2002.

Until last weekend, the Australian Open was his last title success this year, prompting fresh speculation about whether his 29-year-old body was as willing as his mind.

Throughout it all, Federer has remained unfazed, hiding his emotions behind the same calm poker face of someone with a fistful of aces before revealing their hand.

Two weeks ago, he made the final of the Toronto Masters, losing to Andy Murray.

Last week, he went one better and won the Cincinnati Masters.

All of a sudden, talk of his supposed decline has disappeared and he is looming as the form player heading into the US Open brimful of confidence.

"It moves very quickly," he explained.

"I know the rules and how it all works."

Federer has good reason to feel confident about his prospects of winning the last grand slam of the year on the Flushing Meadows hardcourts he has transformed into his private playground.

He won the men's singles title five times in a row between 2004 and 2008.

The only time he has been beaten in the past six years was in last year's final against Del Potro, which went five sets.

The towering Argentine was expected to lead the charge of the new generation this year but has been plagued by injuries and will not defend his title in New York, leaving the old guard of Rafa Nadal, Murray and Novak Djokovic as Federer's most likely threats.

"I guess the top four have the best shot again," Federer said.

Life has gone full circle for Federer since he first came to the United States as just another professional hoping to make it in the Big Apple.

These days he travels with his wife Mirka and their 13-month-old twin daughters, Myla Rose and Charlene Riva, but the demands of fatherhood have not curtailed his boyish enthusiasm for play.

He recently appeared in an online video performing a "William Tell" trick on the set of an advertising shoot. In the video, Federer delivers two powerful pin-point serves that knock a can off the head of a man at distance.

The video became an instant hit and sparked an internet debate about whether the footage was real or had been altered to which Federer offered the same sort of teasing answer he gives his opponents on the court.

"You know how it is with magicians," he said. "They don't tell how their tricks work."