TIME is the one opponent which even the superstars of world tennis cannot defeat. Even if the likes of Roger Federer are giving it a pretty good run for its money.

By the time Andy Murray returns to Wimbledon for next year's Championships he will have blown out the candles on his 30th birthday cake. While there seems little need to look out the pipe and slippers just yet, it is only natural that back surgery and the responsibilities of fatherhood to his first child, Sophia, should bring on occasional thoughts of his own mortality and the need to maximise the finite time he has left at the sharp end of the sport.

In truth, tennis is no longer the young man's game it used to be. No fewer than 49 of the 128 entrants to this year's Wimbledon are thirtysomethings, a record for the tournament. Two of the six major winners in the men's field, Federer and Stan Wawrinka, have tasted major success the wrong side of 30.

But eleven years on from his electrifying debut at this venue as a teenager, the change in Murray is unmistakeable. While he stayed up late on Thursday night, glued to the TV coverage of the Brexit referendum, in general these days he finds himself going to bed early. This allows him to get up earlier in the mornings and spend time with his daughter, before departing to put in another marathon shift in pursuit of further Grand Slam glory. That aside, he plans to change little of his well rehearsed Wimbledon routine for his first championships with Sophia as part of his extended entourage. He will still drive into the All England Club from his home in Oxshott, Surrey, most days.

His friend Tim Henman would be able to tell him all he needs to know about a sportsman's legacy being defined, for good or ill, by what happens one fortnight in June each year. While Henman's four semi-final defeats saw him tagged a perennial nearly man, Murray can already match him for four semi-final defeats and raise him two final appearances, winning one and losing the other. It is an unprecedented haul for a British player in the Open era but the Scot is clearly still hungry for further glory while he is at the peak of his career.

"You do appreciate it more than when you’re young," admitted the World No 2. "When you start to get older you understand the history and the traditions a bit more and realise when you look back on your career that they are the events you will be remembered for. I started to realise how good an opportunity it was, not just to play in those events, but to be in the latter stages of them a lot of the time. I’m aware I need to make the most of every opportunity I get."

And in the unlikely event that he ever is struggling to get out of bed in the morning at least he has the hyperactive example of Novak Djokovic, a whole week younger than him, to keep him on his toes. Along with his brother Jamie, yesterday saw the world's top two tennis players persuaded to pass on their knowledge and experience on a two-year term on the ATP Tour player council.

"I would imagine you think more in those terms when you feel like you’re starting to drop off a little bit, or physically you’re not quite the same, and your results and ranking or starting to drop," said Murray. "Whereas right now I don’t feel that way at all. And obviously me and Novak are one week apart as well. He also seems to be doing fine and showing no signs of slowing down either."

Rather than drain his resources, Murray feels that having Sophia around is a valuable release valve. “Playing still feels the same for me," said the World No 2. "It’s just that every day doesn’t feel the same - especially on days when I get to see her [Sophia] because she is changing all the time, learning new things all the time, and every day is a bit more exciting. Maybe before, when you're doing a practice week, it’s maybe the same thing every single day and can be a bit boring. Now I have something away from the court which takes my mind off tennis but also gives me a little bit of freshness."

Lord knows Andy and Kim still have time on their side before pinning down their progeny - Sophia is just four months old - to a chosen profession, but the World No 2 will preach the health and social benefits of playing sport from an early age and would be delighted if she took as much from it as he clearly does. Sport, of course, runs in the family, with his mum Judy a top tennis player and coach and her grandfather Roy Erskine a talented footballer and tennis player.

“It’s not about tennis, it’s just about trying a different number of sports," said Murray. "Because if you find one that you like often it’s a skill that you have for life. And socially I think it’s great as well. My Dad is in his sixties and he still plays five-a-side football with his friends now.

"Whether she plays tennis or not I don't know but if she enjoys playing then that’s fine," he added. "I think the pressure that kids feel can come from many different things. It doesn’t necessarily just have to be because of what your parents have done in the sport. If she enjoys it and really wants to play then that’s great. But likewise if she hates tennis and finds it boring than that’s cool as well. If she wants to do something completely different and hates sport, then that’s also fine. But when she’s young I’ll try to encourage her to do different sports.”

At the moment his responsibilities are far more basic than that, though. "I haven’t bumped her head on anything yet or dropped her or had her roll off the bed or anything," said Murray. "I was talking to Colin Fleming [the Scottish doubles player, who has an 18-month-old daughter called Rose] about that and he was saying that when he was out with his daughter she always ends up getting a bump or a bruise or something on her head which never happens with her mother. But she’s so small she’s quite easy to manage just now. I’m sure that when she gets a little bit bigger and starts moving around a bit more then I’ll make a few mistakes.”