San Francisco 49ers defensive end Nick Bosa is almost certain to miss Sunday’s game against the Denver Broncos, and general manager John Lynch said Thursday that a firm return date is still not available.
Lynch, speaking on KNBR, said the club wants to “make sure he’s right on all counts” before putting the edge rusher back on the field. Bosa has already sat out Week 3 with the calf injury and remains sidelined as the team works through the middle of the season.
“I think he’s working through it, and when he’s right, we’ll have him back out there,” Lynch said. “I’m not trying to be vague. Calf injuries are sometimes murky.”
The injury occurred during a pre-practice warm-up before a walkthrough, not in a game. Coach Kyle Shanahan has said Bosa will be out a few weeks and is expected to return at some point this season. The team has also discussed whether injured reserve is the cleaner path.
If Bosa is placed on injured reserve, league rules would require him to miss at least four games. Under that timetable, the earliest he could be designated to return would be the Week 7 trip to Atlanta.
Bosa is 28. He has yet to record a sack in the two games he has played this season, and he has two sacks in five games since the start of 2025, according to reporting tied to Adam Schefter. The production dip follows a run of lower-body problems that has limited his availability.
His 2025 season ended in late September after an ACL tear that required surgery. Knee irritation and swelling then cost him time in training camp this year. He opened 2026 on a pitch count over the first two weeks before the calf strain removed him again.
The 49ers’ defensive line was already thin before the latest setback. Rookie edge Romello Height was ruled out of the Week 3 game against Arizona with a hand injury, and several other defensive linemen who made the initial roster have also been unavailable at points this season.
Shanahan has described the calf issue as something the staff anticipated might surface while Bosa worked back from the knee reconstruction. That does not change the immediate problem: San Francisco will face Denver without its top pass rusher.
Lynch’s Thursday comments also covered other absences. Wide receiver Mike Evans (rib) and left tackle Trent Williams (stinger) were both out of practice Wednesday.
Lynch said Evans is “going to make every attempt to try to play” through the rib injury. Williams, he said, could return to practice Thursday, which would put the veteran tackle on a shorter track than Bosa.
Denver presents a different test than the Cardinals game Bosa already missed. The Broncos’ offense will not have to account for the 2019 Defensive Rookie of the Year on the edge, and San Francisco will have to generate pressure with a rotation that has already been shuffled.
Calf strains are difficult to calendar because the muscle is involved in every change of direction a pass rusher makes. Lynch’s description of the injury as murky matches the public timeline Shanahan has given: multiple weeks, not a day-to-day designation.
No practice window or activation date has been announced. The 49ers’ next public injury report will show whether Evans and Williams moved forward and whether Bosa remains listed without a return target.
