Felix's pitching elbow is suddenly a concern. (US Presswire)

A concern about Felix Hernandez's elbow might affect talks with the Mariners about his contract extension, CBSSports.com's Jon Heyman has confirmed. ESPN's Buster Olney first reported the news. A few days ago we learned the two sides were discussing a seven-year deal worth $175 million, which would be the largest pitching contract in baseball history.

Heyman confirmed Felix did take a physical recently, which is when the elbow concerns arose. The two sides are working through various issues, the elbow among them. There is still hope the contract will be completed, but Heyman hears it is "not imminent." Pre-signing physicals, especially for contracts of this magnitude, are standard.

Hernandez, 26, missed close to a month with a flexor strain in his right elbow in 2007. An ankle sprain sent him to the DL briefly in 2008, but otherwise he's been healthy in recent years. Hernandez has thrown at least 232 elite innings in each of the last four seasons, so if his elbow has been barking, he's done a good job of hiding it.

Felix recently declined an invitation to the World Baseball Classic. He was scheduled to become a free agent following the 2014 season, so the proposed new extension would keep him in Seattle through 2019. The two sides could revise the new contract if the elbow problems prove to be anything more than a minor scare.

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