Beijing - Former world number one Andy Murray has brought his season to a premature end, pulling out of the China Open in Beijing after reaching the quarter-finals at the Shenzhen Open.
The 31-year-old Briton is battling to regain top form and fitness following hip surgery in January but British media including the BBC said that he has suffered a minor ankle problem.
Murray was not included when the China Open draw was made on Saturday and also absent was world number three Novak Djokovic, who was offered a wildcard.
The China Open - which begins this weekend - has been hit by several high-profile pull-outs with Rafael Nadal not involved because of injury, Roger Federer saving himself for Shanghai and Serena Williams all absent.
Murray, ranked 311 in the world, previously said that Beijing would be his final tournament this season and he is carefully managing his schedule following his operation in order to get the most out of his creaking body.
He was beaten 6-4, 6-4 on Friday in Shenzhen by Spanish veteran Fernando Verdasco, although he defeated world number 11 David Goffin in the last 16 for the best win since his comeback.
Murray, a three-time Grand Slam title winner, will spend the winter working himself back to the sort of fitness levels that saw him capture nine titles in a stellar 2016 campaign, including his second Wimbledon crown and another Olympic gold.
"It was another three matches, which is positive," said Murray after defeat to Verdasco.
"But obviously I want to play better than that, I have higher ambitions than losing in the quarter-finals. I want to try to be better in these events.
"I need to spend more time on the practice court and the gym so that I'm more robust and physically in better shape."
Juan Martin del Potro, the top seed in Beijing, will play Albert Ramos in his opener.