PHOENIX -- The D-backs' top pick in the First-Year Player Draft has hit a significant snag in beginning his professional career.

Texas A&M junior starting pitcher Barret Loux, the sixth overall selection, failed his physical, ESPN's Buster Olney and FOXSportsArizona.com's Jack Magruder reported on Saturday night.

On Sunday, a club official declined "commenting on the situation until the process is completed." In Magruder's report, interim general manager Jerry Dipoto also declined to offer specifics, though he added, "We love the player."

In 2009, Loux underwent surgery to eradicate bone chips from his right (throwing) elbow, though this past season he went 11-2 with a 2.83 ERA in 17 games -- 16 starts -- for the Aggies. It's not clear if arm trouble is related to his failed physical.

Loux's predicament would likely give the D-backs leverage in contract negotiations. If the club elects not to sign him, it will receive the seventh pick in the 2011 Draft's first round as compensation. Arizona has signed its first Draft choices every year since 2000.

Though he is unlikely to use it, Loux also has one season of collegiate eligibility remaining. He and Arizona have until Aug. 16 to hammer out an agreement.