Seattle finalized Jackson's deal Tuesday, the first day of minicamp. Seattle cleared a roster spot when defensive end Ryan Robinson was waived/injured after rupturing his Achilles tendon last week. Robinson cleared waivers and reverted to Seattle's injured reserve list.
Jackson gives Seattle depth after the team went through most of the offseason with just Wilson and second-year free agent R.J. Archer on the roster after B.J. Daniels was moved from quarterback to wide receiver.
Jackson will spend his fourth season with the Seahawks. He was Seattle's primary starter in 2011, going 7-7 in games he played. He then went to Buffalo before returning to Seattle as Wilson's backup the past two seasons.
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