Marin Cilic withdraws from Australian Open

Marin Cilic has withdrawn from the upcoming Australian Open due to a shoulder injury.

The US Open champion, 26, has been struggling with the problem for over a month.

He has now been forced to pull out of the first Grand Slam of the season on the advice of doctors.

"I have a right shoulder injury which has hampered me for some time now," the Croatian said in a statement. "It is improving day by day, but I still don't feel fit enough to be able to compete at the highest level."

The Australian Open gets underway in Melbourne on January 19.