The third-year tight end has missed three consecutive games after leaving the team's Week 2 contest against the Arizona Cardinals with a right ankle injury.
He had limited participation in practice both Wednesday and Thursday.
Hernandez is one of 14 Patriots listed as questionable for Sunday's game. The list includes tight end Rob Gronkowski (hip), guard Logan Mankins (calf/hip), right tackle Sebastian Vollmer (back/knee), linebacker Dont'a Hightower (hamstring), running back Brandon Bolden (knee) and wide receiver Julian Edelman (hand), who returned to practiced this week after suffering the injury in Week 3.
The Pats were expected to travel to Seattle on Friday, and coach Bill Belichick said Hernandez could be a game-time decision.
"We'll just have to see how it goes here," Belichick said Friday morning. "He practiced late last week and did some things yesterday and Wednesday. We'll see how he is today and see if it set him back, or didn't set him back, and how that went. We'll have the day to evaluate it on Saturday, and we'll see where we're at on Sunday. It could be a game-time decision."
Field Yates is a regular contributor to ESPNBoston.com.