Australia’s Samantha Stosur was forced to withdraw from her Indian Wells quarter-final match against Angelique Kerber due to a right calf injury on Thursday.
Former US Open champion Stosur was seeded seventh and held a 2-0 career record over fourth-seeded German Kerber, who now receives a walkover into the semi-finals.
Stosur, the world No.9, had looked in good form at the tournament and was eying her first semi-final appearance in five months.
Stosur had on Wednesday recorded a rare comeback win in the fourth-round, rallying from a set down to beat German youngster Mona Barthel 4-6 6-2 6-3.
But revealed it was in the final game of the match that she suffered the injury.
“I hurt my right calf muscle in the last game of my match against Mona Barthel when I was serving for the match, so I don’t know if you can get any more unlucky than that,” said Stosur.
“I think we only played another four points in that match. I felt something go in my calf and it was hurting a fair bit. Yesterday I took the day off practice and only did treatment, probably iced it about 10 times.
“This morning I thought I would give it a shot, and tried to go out and warm up, and after about five minutes I knew that there was no chance I could play, unfortunately.”
The last time Stosur progressed past the quarter-finals of a tournament was in Moscow last October where she lost to Caroline Wozniacki in the title match.
The injury has also put a cloud over her participation in the Miami WTA event which takes place later in the month.
“I’ll talk to the physios and the doctors and work out a good plan for how many days I need to take off and go from there,” said Stosur.
“It’s all a bit up in the air at the moment because I’ve never been through this type of injury before, so it’s a matter of wait and see, talking to the people who know and reassessing each day.”
Kerber will face either world No.1 Victoria Azarenka or Wozniacki in the semis.