Hart was ruled out with a hamstring injury for the remainder of Sunday's game versus the Saints, Curtis Crabtree of Fox 13 Seattle reports.
Hart did not record a catch before exiting with a hamstring issue at some point during Sunday's game, though the exact severity of this issue is still unknown. The 26-year-old wideout recorded one reception while playing eight offensive snaps over the first four weeks of the season, and his next chance to play will come against the Cardinals on Oct. 16.