Roger Federer expressed his hopes for former rivals Novak Djokovic, Rafael Nadal and Andy Murray to "keep playing forever", insisting the ATP Tour is "better with them".

Federer called time on his glittering career in 2022, while the other three - who between them formed tennis' 'big four' - appear not to be far away from joining him in retirement.

Nadal, who will miss Wimbledon to focus on his "last Olympics", and Murray are expected to hang up their racquets this year, with the latter revealing in February that he does not "plan on playing much past this summer".

Meanwhile, 24-time major winner Djokovic is also likely be absent from the grass-court major, having undergone knee surgery following his withdrawal from the French Open last week. 

Now in their late 30s, all three players are certainly at the twilight of their remarkable careers.

But Federer, who says the quartet all now "get on super well" after years of rivalry, hopes they are not finished just yet.

"I really don't think there are any words of advice that I can give him," he told BBC Sport. "Retirement is so deeply personal. When you take that decision, everybody is in a completely different circumstance.

"We've gone through similar things, but I'm too far away to give advice. If [Andy] called me up, I'd be happy to answer some questions. He's had this massive hip issue and what he is doing is inspirational.

"I hope Andy, like Rafa and Novak, can keep playing forever, like a fan. The tour is better with them. I was watching Roland-Garros last week, and I was like: 'Wow, they're so good - I used to do that too!'

"It's tricky sometimes and there’s definitely moments when you don't like a certain opponent, but then you like him so much. It's important to remember this as a player - it is just tennis and, in the end, we can be normal.

"You see us being super friendly with each other after the rivalry, and we get on super well."