Injuries have once again become an issue for Milos Raonic, as Canada's top-ranked tennis player has withdrawn from Masters 1000 events in Madrid and Rome with a banged-up right knee.

Tennis Canada announced Raonic's withdrawal from the clay-court tournaments Monday.

It remains to be seen whether the world No. 16 will be ready for the French Open, which starts May 26. Raonic withdrew from the second Grand Slam of the season last year, as well as the Rome Masters, with a right knee ailment.

It's a blow to the hard-serving Canadian from Thornhill, Ont., who had some success at hard-court tournaments earlier this year. He reached the Indian Wells semifinals last month, losing to eventual champion Dominic Thiem.

Raonic hasn't played since losing in the second round of the Miami Open to Britain's Kyle Edmund on March 24.

Skipping the clay season to recover is not necessarily a bad thing for Raonic. His powerful game is much better suited to grass and hard-surface courts, though he did reach the semifinals in Rome in 2014.