Horton (shin/groin) has been ruled out for Sunday's game at Tennessee, Michael-Shawn Dugar of The Athletic reports.
Horton's absence from a third straight game comes as no surprise after reports last week suggested he was a candidate for injured reserve. It shouldn't matter much for Seattle's offense unless Jaxon Smith-Njigba, Rashid Shaheed or Cooper Kupp miss time with an injury.