Seattle CB Richard Sherman hopeful about appeal

Seattle CB Richard Sherman hopeful about appeal
Seattle Seahawks' Richard Sherman motions to fans after intercepting in the end zone against the San Francisco 49ers in the second half of an NFL football game, Sunday, Dec. 23, 2012, in Seattle. The Seahawks won 42-13. (AP Photo/Elaine Thompson)

SEATTLE (AP) — Seahawks' cornerback Richard Sherman says there was a "chain of custody" mistake that led to his positive test for performance enhancing substances, and was the basis of his appeal.

Sherman spoke about his appeal after the Seahawks' 42-13 win over San Francisco on Sunday night. Sherman had an interception and returned a blocked field goal 90 yards for a touchdown in the blowout victory.

Sherman missed two days of practice this week while his appeal was heard. He doesn't know when a decision would come, and added he would pursue the appeal further if he can. He doesn't know how far he can take it.

Sherman said there were mistakes by the tester. If the NFL upholds Sherman's four-game suspension he would miss the playoffs.