Macklin had started 32 of 33 games since he signed with Arizona in 2004. But the right cornerback dropped a possible interception on the third play of last week's 34-27 win over San Francisco, then missed a tackle on 31-yard touchdown run by Vernon Davis for the game's first score.
Eric Green replaced Macklin and played the rest of that game. Green, a third-round draft choice in 2005, was starting for Macklin on Sunday.
Seahawks defensive tackle Russell Davis also was inactive. The former Cardinals player was optimistic last week that plantar fasciitis in his foot would be healed so he could make his Seattle debut. Davis was injured in the exhibition opener Aug. 12.
Seattle wide receiver Deion Branch remained exempt from the roster after his trade last week. The NFL granted Seattle a two-week exemption for the former Super Bowl MVP, acquired from New England, to get acclimated to his new offense.