MONTE CARLO — Canadian tennis star Milos Raonic pulled out of the Monte Carlo Masters on Thursday with a right knee injury.
Raonic, from Thornhill, Ont., withdrew from the tournament just before his third-round match against second-seed Marin Cilic.
It was not immediately clear how Raonic injured his knee.
The injury is the latest in a series of frustrating ailments that have plagued the hard-serving Canadian.
Raonic had right hip surgery in 2011, right foot surgery in 2015 and left wrist surgery last year. He also struggled with a right leg injury for much of last year, missing a stretch of tournaments including the U.S. Open.
He had plunged from a career-high No. 3 the rankings to as low as 40 earlier this year, but came into Monte Carlo ranked 22nd after reaching the quarterfinals of the Miami Open and the semifinals at Indian Wells.