Marin Cilic's persistent shoulder problems have forced the US Open champion to pull out of the Miami Open later this month.
The big-serving Croatian reached the quarter-finals of the ATP 1000 event in 2013, but has only played once on tour this season due to injury.
Cilic suffered with the injury throughout the second-half of 2014 but was able to compete in the ATP World Tour Finals in London - where he lost all three matches.
The 26-year-old made his comeback at Indian Wells last week, but was beaten in straight sets by Juan Monaco.