Short-handed at cornerback in the face of at least one suspension and perhaps two, the Seattle Seahawks announced Tuesday they've signed cornerback Perrish Cox.

Cox, 26, appeared in nine games as a reserve for the San Francisco 49ers this season before being cut Nov. 13.

He takes the roster spot vacated by cornerback Walter Thurmond, whose four-game suspension for violating the NFL's substance-abuse policy became official Tuesday.

Thurmond, a key reserve, will be eligible to return to the roster Dec. 23.

Starting cornerback Brandon Browner is facing a one-year ban for violating the substance-abuse policy, a person with knowledge of the situation told USA TODAY Sports on Monday.

Browner is going through the process of appealing the suspension, according to the person, who spoke on condition of anonymity because of confidentiality rules with the NFL's drug program.

Thurmond's suspension was first reported by NFL.com over the weekend. Thurmond took to Twitter and apologized on Sunday, writing, "Yes I made a mistake and I have to live with the consequences. I'm disappointed in myself for letting my teammates and family down."

Thurmond has started three games this season for Seattle, including the team's last game against Minnesota when he had his first interception of the season and returned it 29 yards for a touchdown. Even when he wasn't starting, Thurmond was a critical member of one of the NFL's best secondary units as the fifth defensive back in passing situations.

With Thurmond and Browner out, the Seahawks are likely to lean on young backups Byron Maxwell and Jeremy Lane.

Contributing: Wire reports
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