Britain's Emma Raducanu has withdrawn from the Miami Open in the United States with a lower back injury.
The 21-year-old was scheduled to play China's Wang Xiyu in the first round on Tuesday.
It is a blow to Raducanu's comeback following an injury-disrupted 2023 season.
The 2021 US Open champion was beaten in straight sets by world number two Aryna Sabalenka in the third round at Indian Wells last week.
It is not known how serious Raducanu's injury is, or whether it will impact her selection in Great Britain's Billie Jean King Cup squad for their qualifying-round tie with France from 12-13 April.