World number one Andy Murray thinks he may only have a "couple of years" left of competing at the highest level.
Murray won his third grand slam in 2016 and dethroned Novak Djokovic at the top of the rankings during a phenomenal end to the year that saw him follow-up a run of four straight titles with glory at the ATP World Tour Finals.
Although Roger Federer, who turns 36 in August, took his majors tally to 18 with victory at the Australian Open, the 30-year-old Briton does not expect to still be competing at such a level when he reaches that age.
"My coach, Ivan Lendl, was still competitive at the top until he was about 32 but, generally, over the past 20 to 30 years, normally by early 30s is when players have struggled to stay at the top," Murray said in an interview with BBC Sport.
"I know some of the players have been doing really well until their mid-30s recently, but that might not be the case with me. Maybe the next couple of years are the last few where I have a chance to compete for the majors and the biggest tournaments.
"Most of the players are travelling with physios now, spending a lot more time working in the gym to protect their bodies from the kind of pounding you give it on the court as well. I think some of that explains it.
"I don't know how long I'm going to be playing for any more. I want to make the most of every tournament I compete in. If I'm going to be away from my family, I'm not going to do that and not do my best, be totally professional and take every tournament as seriously as I can.
"I'll continue to play and so long as my body is fine. I would like to hope that I would continue to do that whilst I'm still enjoying it.
"I enjoy being away from the court. I have a family now - I have more interests away from the court than I did in my early 20s or mid 20s - so obviously it will be sad to stop. But I think I'll be all right."
After a disappointing start to 2017 that has seen Murray struggle with injury, he reached the semi-finals of the French Open before losing to Stan Wawrinka.
Assessing his chances of triumphing at Wimbledon again to equal the great Fred Perry with three triumphs at the All England Club, he said: "It would be amazing, I never expected to win it once, never mind twice. It had been such a long time since any British man had won that.
"I'll give it my best shot for sure. I'll prepare as best I can and if I play well then I definitely have a chance of winning.
"Form can turn around very quickly providing you're mentally in the right place and you're doing the right things and training. And I feel I'm in a good place now to go on a good run during the grass."