World number two Roger Federer claims that while he knows he will have to retire sooner or later, he is happy with his current situation.

The 19-time Grand Slam champion most recently defeated long-time rival Rafael Nadal for the fourth time in a row in 2017, winning his sixth title of the year in Shanghai.

It only continues what has been a remarkable turnaround for Federer, who took time off to recover from a knee injury in 2016, and has been reaping the benefits this year.

Not only does the Swiss ace have a Tour-best six titles – tied with Nadal – but he has also split the Grand Slams with the Spaniard, winning the Australian Open and Wimbledon, his first major titles since 2012.

At 36 years of age, such a season might be hard to emulate again and Federer acknowledges that fact by stating that he will only keep playing if four things in his life continue to work.

"I know it (retirement) is sooner or later," he told Gulf News. "I know I'm not 22 anymore, but I don't have a date.

"If the body allows me to play, my family allows me to play, if the success is still there, if I'm happy to travel, I will continue. But the four things have to work, if one of the four doesn't work, it maybe the time to stop. But for now, it's ok."

Federer notably skipped the entire clay-court swing in order to be fresh for the grass-court season and went on to credit the break for his success.

"For me, I have come to realise that sometimes less is more," he explained. "Today, I think when I take enough rest, feel hungry and have the fire, then it's the one I can play my best.

"I want to make sure I'm happy to be on the court and happy to do press. It's like if I do too much, the fire is like Juuuu... it goes away. So for me, the family is my priority and then the rest."

The Wimbledon champion is idolised by many youngsters currently on the ATP Tour who have struggled to win the Grand Slams thanks to the Big Four's dominance. If they want to become tennis legends in the future, they need to get a lot of things right, according to Federer.

"(To be legends), you need hard work, passion, and a good team, good training facilities, and being able to withstand pressure, and understanding the Tour, making it like the second home," he added.

"It takes a little bit more time, but they are doing great. It's nice to see these young talents in the Tour, and they make tennis a better place and exciting for fans."