Andy Murray knows time is no longer on his side as the 36-year-old conceded that another deep run at a major may not be within his reach after exiting the US Open on Thursday.
The 2012 champion put up a tough fight at first against 19th seed Grigor Dimitrov but rapidly lost energy and appeared to have little left in the tank as he conceded the second-round match with a double fault.
"It's obviously disappointing, to not play how you would like," the Briton told reporters.
"Maybe I need to accept that, these events, I had the deep runs and everything that I felt like I'm capable of, they might not be there, as well."
The three-times Grand Slam winner nearly retired in 2019 due to a hip issue but played some of his best tennis in years this season.
He reached the Doha final and proudly noted after his opening win at Flushing Meadows that he was at his highest ranking - 37th - since having a metal hip put in.
But he only made it as far as the third round of the Australian Open and exited Wimbledon in the second.
"I still enjoy everything that goes into playing at a high level. I enjoy the work," Murray said.
"The training and trying to improve and trying to get better, I do still enjoy that. That's what keeps me going."
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