British number one Emma Raducanu was forced to retire from her Italian Open first-round match when she was again hampered by a back injury.
Raducanu has been managing the issue in recent weeks but, after needing off-court treatment, could not continue against Canada's Bianca Andreescu.
The 19-year-old trailed 6-2 2-1 in Rome when she decided to stop.
It is the latest of a series of niggles that have dogged the US Open champion in her first full year on the WTA Tour.
Raducanu, ranked 12th in the world, will be hoping the injury improves before the French Open starts.