49ers star tight end George Kittle is expected to miss eight weeks with a broken bone in his left foot, according to ESPN's Adam Schefter.
According to NFL Network's Ian Rapoport, he will be placed on injured reserve.
Kittle appeared to injure his foot early in the fourth quarter of Sunday's eventual 37-27 defeat to the Seahawks when the Iowa product leaped to catch a 25-yard pass from quarterback Nick Mullens.
The two-time Pro Bowler tight end came down awkwardly and hobbled to the sidelines.
Kittle finished with two catches for 39 yards in the loss.
He has already missed Weeks 2 and 3 of the 2020 season with an MCL sprain.
If Kittle were to miss eight weeks, the earliest he would return is in Week 17 vs. the Seahawks.
San Francisco is currently 4-4 and in last place in the NFC West.
In each of Kittle's last two seasons, the All-Pro tight end finished with more than 1,000 receiving yards and at least 80 catches. This season, he has just 37 catches for 474 yards and two touchdowns.
Kittle's injury is also just the latest on a growing list of 49ers absences. Quarterback Jimmy Garoppolo is reportedly expected to be sidelined indefinitely with a high ankle sprain. Garoppolo, like Kittle, left Sunday's loss early.
Nick Bosa, Richard Sherman, Solomon Thomas, Dee Ford and Raheem Mostert are just some of the other 49ers players that are on injured reserve this season.