The New York Jets feared the worst when safety Antonio Allen went down with a non-contact injury on Thursday. The initial concern was that Allen tore his Achilles' tendon, an injury that would sideline him for the entire season.

On Friday, those fears were confirmed when an MRI revealed Allen did indeed tear his Achilles' tendon.

Allen was a valuable backup for the Jets last season -- and a versatile one. He played both cornerback and safety, providing flexibility when called upon.

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After starting eight games last season, new head coach Todd Bowles planned on using Allen primarily as a safety, given the crowded depth chart at cornerback. Now, Bowles has to find a replacement for the fourth-year safety to play behind Calvin Pryor and Marcus Gilchrist.

It's particularly a big blow for Allen, as he was entering the final year of his contract. He was looking to earn his way to a big paycheck after being a seventh-round pick in 2012.