Vannett suffered a shoulder injury in Sunday's game against the Rams and is doubtful to return, Bob Condotta of The Seattle Times reports.
Vannett is mostly a run-blocking tight end, so his absence shouldn't affect the Seahawks' offense significantly, especially with a pass-heavy approach in place with the team trailing the Rams by a large margin. Jimmy Graham and Luke Willson are the only healthy tight ends remaining on Seattle's roster.