US Open champion Marin Cilic will miss the Australian Open with a shoulder injury.
The Croatian has withdrawn from the tournament, which gets under way in Melbourne on January 19, because of a problem with his right shoulder.
The world number nine said he made the decision after being advised by doctors that playing with the injury could lead to an even longer lay-off.
He said in a statement on his official website: “I am really disappointed to announce that I had to withdraw from the Australian Open. Right shoulder injury, that hampers me for some time now and forced me to withdraw from the ATP event in Brisbane, is improving day by day, but I still don’t feel fit enough to be able to compete at the highest level.
“I am really sad that I won’t be able to participate in Melbourne, especially after winning the last grand slam in New York, but I was advised by doctors to be careful as much as possible to avoid even more serious problems.
“I have received lots of support letters from my fans worldwide lately and I am grateful for your support and best wishes. I was really looking forward to be back on court in Australia and now I hope we will meet very soon in Zagreb.”
Cilic’s withdrawal follows that of France’s Jo-Wilfried Tsonga, who pulled out with an arm injury.
Both players took part in the inaugural International Premier Tennis League, despite their problems, and that decision looks like it may have cost them their chance in Australia.
It should provide some good news for British number two James Ward, though, who is likely to gain a place in the main draw of a grand slam without a wild card for the first time.