NEW YORK (WFAN/AP) – Phil Hughes’ “dead arm” is still a mystery, but the Yankees might finally be on track to finding an answer for the young right-hander.

Manager Joe Girardi said a battery of tests on Wednesday revealed that Hughes has a low-level risk of thoracic outlet syndrome, a circulatory problem.

“I think anytime you talk about circulation problems, there’s some concern,” said Girardi. “This is different than (the aneurysm David Cone) had. These are different types of things, but there’s always a concern.”

The team will send him to St. Louis to see a specialist, Dr. William Thompson.

“I think you wait to see what the specialist says,” said Girardi, “to determine if he has it or doesn’t have it, and then you go from there.”

The right-hander had two MRIs and a vascular test to check circulation Tuesday. On the disabled list since April 15 because of a “dead arm,” Hughes cut short a bullpen session Monday, saying his arm didn’t feel any livelier.

Hughes, 24, was 18-8 with a 4.19 ERA last year, earning his first All-Star selection. This season, he is 0-1 with a 13.94 ERA after three starts and has had trouble reaching 90 mph with his fastball.

Will the Yankees’ rotation be OK without Hughes? Sound off in the comments below…

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