Garbine Muguruza bowed out of the Dubai Tennis Championships on Tuesday after the French Open champion was troubled by an Achilles injury in her second-round match against Kateryna Bondarenko.
The powerful fifth seed was 4-1 down in the first set when she retired from the WTA Premier tournament in the United Arab Emirates.
Spaniard Muguruza revealed she had felt pain in her left Achilles following a loss to Zhang Shuai at the Qatar Open last week and had the same issue against Bondarenko.
The world number seven also pulled out of the Brisbane International when she was losing by the same margin in her semi-final with Alize Cornet due to a thigh injury.
Muguruza struggled with injury during her run to the quarter-finals of the Australian Open and has now suffered another setback.
"When I finished in Doha, because of the rain, a lot of people played two matches, including me," Muguruza said. "The second one was very tough, and I remember that as soon as I went, after the match, to my room, I started to have a pain in my left Achilles.
"The next morning was even more painful. I have carried this since that day. And here, I have been training but on and off, honestly, because of the pain.
"Some days it was a little bit better, some days it was a little bit worse. It was just hard for me to serve, especially, and to just move side to side today on the court.
The Venezuela-born 23-year-old will go for a scan, but is optimistic that she has not done serious damage.
"I can't see anything right now. I have to do some kind of MRI," she explained.
"Personally, I don't think it's something big, hopefully, but it's very irritating and it's really bothering me every time I have to run on the court."