Barty, the 2019 French Open winner, was leading 6-4 2-1 against her American opponent when she called a physio and had her right-arm strapped with a compression sleeve.
World number one Ash Barty was forced to retire from her Italian Open quarter-final against Coco Gauff with an arm injury, raising doubts about her participation at the French Open.
Australia's Ashleigh Barty after retiring from her quarterfinal match against Coco Gauff (REUTERS)
Barty, the 2019 French Open winner, was leading 6-4 2-1 against her American opponent when she called a physio and had her right arm strapped with a compression sleeve.
The Australian eventually decided against continuing the match in wet conditions in Rome, allowing Gauff to book a place in the final four.
Barty missed the 2020 claycourt swing due to the COVID-19 pandemic but has returned even stronger this season, winning the title in Stuttgart before finishing runner-up to Aryna Sabalenka in Madrid last week.
The 24-year-old now faces a battle to prove her fitness before the French Open, which begins on May 30 in Paris.
Meanwhile, Gauff has progressed to her first WTA semi-final on red clay at the age of 17. She will face the winner of the quarter-final between reigning French Open champion Iga Swiatek and Elina Svitolina.
Stay updated with the latest sports news, including latest headlines and updates from the Olympics 2024, where Indian athletes will compete for glory in Paris. Catch all the action from tennis Grand Slam tournaments, follow your favourite football teams and players with the latest match results, and get the latest on international hockey tournaments and series.