Emma Raducanu lasted only seven games of her first-round match at the Nottingham Open, where she made her WTA Tour debut a year ago.
US Open champion Raducanu was back in Nottingham as she prepares for a second Wimbledon campaign.
The 19-year-old made a name for herself with a run to the fourth round at her home grand slam in 2021, before she sensationally triumphed at Flushing Meadows.
Having seemingly established herself as the next superstar of women's tennis, Raducanu has since not found life quite so straightforward.
"It has been a really tricky 12 months, to be honest," Raducanu told the BBC on Tuesday before her match against Viktorija Golubic. "It hasn't always been easy."
And this was anything but easy for the second seed, who required treatment on an apparent side injury as soon as after the third game.
Raducanu and Golubic had traded breaks before that medical timeout, and the Briton then quickly broke again.
But she continued to encounter problems and dropped serve twice – either side of further medical treatment – before finally retiring 4-3 down.
Raducanu is scheduled to play the Birmingham Classic next week but will first now have to consider her fitness just 20 days out from the start of Wimbledon.