Emma Raducanu suffered an injury scare just four days before the French Open begins as the Briton lost to Danielle Collins in Strasbourg.
The 22-year-old produced an excellent first set but needed treatment on a lower back issue after falling 5-0 behind in the second.
Seemingly uninhibited by the problem on her return, Raducanu came back from a break down in the decider - but Collins rallied again to win 4-6 6-1 6-3 and reach the quarter-finals.
Raducanu had taken a wildcard into the clay-court event in Strasbourg to get more practice on the surface before the French Open starts on Sunday.