London - He's won seven Wimbledons, 18 Grand Slams, earned over $100 million and been lauded as the greatest player of all time.
However, even Roger Federer can't give birth although that hasn't stopped him thinking about what it might feel like if he could.
The Swiss star is father to two sets of twins with his wife Mirka.
He was asked if he admired the fact that former world number one Victoria Azarenka had returned to the tour just six months after giving birth to her son Leo.
"It's a totally different ball game what she's going through than what I did. I was just there supporting my wife," said Federer.
"I didn't go through it myself even though that would be quite an experience, I guess."
Federer has been praised for juggling his career and for being a dad of four children.
But Azarenka said that it's the women who have the toughest job - for obvious reasons.
"Roger definitely has not inspired me. No disrespect to him, and I think it's amazing, you know, but it's a little different for him," said Azarenka.
Federer didn't take offence and was all praise for the Belarusian.
"I always admire what they have to go through and, you know, just imagine going into practice right away shortly after that," said the 35-year-old.
"It's what she knows best. The body tells her when she's ready to do it again. I find it unreal that she's back playing. I admire her courage."
While appreciating the physiological differences, Federer still pleaded the case for tennis dads.
Andy Murray and Novak Djokovic are both fathers with another child each on the way while Stan Wawrinka has two children.
Murray's third round opponent on Friday, Fabio Fognini is also a recent dad with former US Open champion Flavia Pennetta.
"Having family and playing at the same is possible. I show it. And I'm not the only one. In the top 5 we have other guys who do it exactly like I do, as well," said Federer.
"Maybe they don't have as many kids as I do. But it doesn't change. One kid can scream as much as four kids sometimes."
Federer, the seven-time Wimbledon champion, was speaking after reaching the third round for the 15th time with a 7-6 (7/0), 6-3, 6-2 win over Dusan Lajovic of Serbia.
The third seed will face Germany's Mischa Zverev for a place in the last-16.
He boasts a 4-0 career record over the left-handed serve-and-volleyer including a straight sets win on grass in Halle last month.