Injury-plagued Andy Murray admitted on Monday it might not be realistic to expect him to recapture the golden days when he won three Grand Slam titles.
Murray is on the comeback trail again at Queen's Club in London this week after another round of the fitness issues that have troubled him for several years.
The 34 year-old Scot faces Benoit Paire on Tuesday at the Wimbledon warm-up event, which he has won five times. It will be his first singles match on grass for three years.
Asked on Monday if he felt capable of getting close to the form that took him to the world number one ranking in 2016, Murray struck a downbeat tone.
"I feel OK. I don't feel perfect, but I've been practising well over the last month or so, pretty consistently," he said.
"The question mark is obviously whether the body holds up and I can't say with any great certainty right now whether that's going to happen or not.
"I have been feeling good at different points throughout the last nine months or so, practised really well, felt good going into tournaments. Then, you know, something's happened."
Murray, currently ranked 124th in the world, won the US Open in 2012 and lifted the Wimbledon trophy in 2013 and 2016.
But, beset by hip problems and other issues, he has competed in just two of the past eight Grand Slams.
While Murray's hopes of returning to the top are fading, his old rivals Novak Djokovic and Rafael Nadal are still at their best.
Djokovic saw off Nadal in four sets in a thrilling French Open semi-final last week before claiming his 19th Grand Slam title against Stefanos Tsitsipas on Sunday.
Murray, who has not reached a Grand Slam final since 2016, admitted he had been jealous watching the 34-year-old Djokovic do battle with the 35-year-old Nadal.
"It was an incredible match," said the Scot. "You know, there is a bit of me that's jealous watching that, like I would love to be playing in those matches.
"I would love to still be competing with them in semis of slams, I would love that.
"You know, you can still do things on the court outside of winning slams or competing with those guys."
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