Milos Raonic has withdrawn from the Miami Open with a hamstring problem.
The third-seeded Canadian was due to take on American qualifier Jared Donaldson in the third round of the competition, but was forced to bow out when an existing injury recurred.
"It's related to the previous injury I sustained almost four weeks ago in Delray Beach," Raonic told reporters.
"It's the same muscle in the hamstring up high. It got progressively worse after my first round. It seemed like it was not possible for me to compete today without putting myself at significant risk."
Raonic added that he will not return to action until he is "100% fit", which he expects will be at least two weeks' time.