Naomi Osaka was forced to pull out of the Japan Open ahead of the quarter-final due to a left leg injury.
The former world no. 1 was set to face Jaqueline Cristian for a semi-final on Friday, October 16, but had to be sidelined due to injury, with the Romanian star advancing to the next stage.
During her Wednesday match against Suzan Lamens, Osaka needed painkillers and competed in the match with strapping on her left thigh to complete a three-set.
The Japan Open made the announcement on X, noting, "We regret to announce that Naomi Osaka has not recovered from a left leg injury sustained during the second round of this tournament and has withdrawn from the quarter-finals scheduled for today."
It is not confirmed if Osaka will play in the Pan Pacific Open in Tokyo later this month.
The four-time Grand Slam champion is the latest high-profile player to suffer late-season injury issues.
In September, Iga Swiatek complained the season is "too long and too intense" following a string of injuries among players at the China Open.
British number one Emma Raducanu was also forced to end her season on Thursday after retiring from her two previous matches with illness.
Australia's Daria Kasatkina, Spain's Paula Badosa, and Ukraine's Elina Svitolina also ended their seasons early in recent weeks.
