Emma Raducanu continued to struggle to adjust to the intensity of a full tennis season as she retired injured during the Italian Open.
The US Open champion, who is playing he first clay season, was up against another winner at Flushing Meadows, Bianca Andreescu in the first round.
She was only able to make it through to midway through the second set though, as she withdrew whilst 2-6, 1-2* down.
The problem appeared to be a lower back concern, with her calling the physio on court before telling the umpire "I can't move" and ending the match.
"[I'm] definitely disappointed with how today went," she said afterwards.
"But I wanted to give it a try. I never really knew how bad it was until I went out there.
"I'm still learning when it's right to push my body and push through it and when's not. I guess that's something I'm learning at these tournaments."
The injury is an obvious concern for Raducanu, who will be tackling her first French Open in just two weeks.
From there she will move on to grass court season, with an appearance in Birmingham already confirmed in the lead-up to Wimbledon.
However, back injuries are always unpredictable, and Raducanu now faces an anxious wait ahead of the blockbuster summer schedule.
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