Nick Kyrgios is a major doubt for the French Open after being forced to pull out of the Madrid Open due to his ongoing elbow problems.
The Australian number one has only played two tournaments since picking up the injury during his country's Davis Cup clash with Germany in January, only winning three matches.
He suffered a last-16 exit at the Miami Open and was knocked out of the US Men's Clay Court Championship in the quarter-finals by Ivo Karlovic.
However, his next event on the ATP Tour remains unclear after having a cortisone injection to try and resolve the issue in his arm.
Kyrgios has withdrawn from the ATP 1000 event in Madrid to try and be ready for Roland Garros, but given there are only two weeks between the two tournaments he could struggle to be fit.
In a Twitter post, the 22-year-old wrote: "As most people know, I have been battling an elbow injury since the Australia v Germany Davis Cup tie in Brisbane.
"I have done everything in my power to overcome this organically through rehab, rest and treatment but have still been suffering with pain and been unable to play anywhere near the level I need to be at to compete at the highest levels.
"I have now taken the advice of my physio and medical advisors to have a cortisone injection directly in to the elbow.
"This means that I will be unable to play in Estoril or Madrid which I am really disappointed about.
"I'm sorry to my fans in both Estoril and Madrid but I have to get my elbow right so I can perform at the required level."
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