Britain's Emma Raducanu has withdrawn from the Miami Open on the eve of her first-round match due to a lower back injury, multiple news outlets reported on Monday.
The former US Open champion missed most of last season after having surgeries on her ankle and both wrists.
The 21-year-old was looking to build on her performance at Indian Wells, where she played well but lost in the third round to world number two Aryna Sabalenka last week.
Raducanu received a wildcard into the main draw at the Miami Open and was scheduled to face China's Wang Xiyu in their first round match on Tuesday.
Raducanu, who in 2021 became the first qualifier to win the U.S. Open, is scheduled to play in Britain's Billie Jean King Cup tie against France next month.