Roger Federer believes becoming a father of twins keeps his love of tennis alive, so much so that retirement still remains way off his radar even if he is 32 and his powers appear to be waning.
This time last year, the 17-time Grand Slam title winner was paying fulsome praise to contemporary Andy Roddick, the man he had defeated in three Wimbledon finals, when the American quit.
On Tuesday, he was expressing similar support to another long-time American rival, James Blake, who has also announced his retirement from the sport at the US Open.
Blake is just eight months older than Federer, but the Swiss star insists he has no intention in calling a close to his career.
"Clearly when you win everything, it's fun. That doesn't necessarily mean you love the game more. You just like winning, being on the front page, lifting trophies, doing comfortable press conferences. It's nice," said Federer.
"But that doesn't mean you really actually love it. That maybe shines through maybe more in times when you don't play that well. For me, I knew it, winning or losing, practice court or match court, that I love it."
His twin girls, Myla Rose and Charlene Riva, have just turned four.
When they were born in July 2009, Federer admitted that he wasn't sure how being a father would impact on his career.
But despite now standing at seven in the world -- his lowest ranking for a decade -- and having lost in the second round at Wimbledon, which ended a run of 36 successive Grand Slam quarter-final appearances, Federer intends to keep playing.
"Clearly when I had my two girls, I wasn't sure right off the bat how it was going to be after that. Was I going to be able to play the same schedule? Was my love for the game as big? Were we going to be able to cope with the whole thing, having twins or not?" he said.
"But we managed it totally fine. They were at the court today. I'm so happy to see them before and after the match. I'm in a good spot right now. I want to enjoy it as long as it lasts."
Now in his 16th year on the tour, Federer believes that his girls also allow him to view the familiar surroundings of the tour in a new light, something from which they all benefit.
"They're learning as we go along, just getting to meet so many different people, cities and countries and languages, places and travels," he said.
Federer, a five-time US Open champion, reached the second round on Tuesday with a 6-3, 6-2, 7-5 win over Slovenia's Grega Zemlja, firing 12 aces and 35 winners.
He now tackles Argentina's Carlos Berlocq for a place in the last 32.