Even before being sidelined, Bosa had been limited in practice and held out of team drills as he continues working his way back from last season's ACL injury.
On Saturday, 49ers head coach Kyle Shanahan didn't sound overly concerned about his star pass rusher's status.
"He was doing great, and then he got sore just going through some of the individuals," Shanahan said. "I mean, you wish that didn't happen, but no, there's no concern to where something's happened that is a big setback or anything.
"But we're waiting until the soreness goes away and evaluating why the soreness has happened, but I still feel pretty good about that."
Also missing from the start of Monday's practice were wide receivers Mike Evans (quad), Christian Kirk (calf), and De'Zhaun Stribling, according to multiple reports. Stribling had previously returned to practice after dealing with hamstring tightness.
Update: Stribling did end up practicing.
Additionally, running back Christian McCaffrey was not on the field when practice began, adding another notable absence to the 49ers' offense. The team announced that McCaffrey is dealing with "tightness" and was given the day off.
There was some positive news, however. Tight end George Kittle (Achilles) appears to be making good progress during individual work on the side and could be nearing a return to practice. He remains on the physically unable to perform (PUP) list.
49ers rookie offensive lineman Carver Willis also returned to practice after clearing the concussion protocol.
Related News
More San Francisco 49ers News
-
49ers' John Lynch on chances Mike Evans plays vs. Broncos, Nick Bosa and Trent Williams updates
San Francisco 49ers wide receiver Mike Evans is working through a rib injury he suffered Sunday against the Arizona Cardinals. There is no guarantee that he will be healthy enough to suit up for this weekend's contest against the Denver Broncos, but the 49ers are hopeful. It... -
49ers vs. Broncos injury report: Thursday practice brings several updates
The San Francisco 49ers are preparing for their Week 4 contest against the Denver Broncos on Sunday at Levi's Stadium in Santa Clara, California. Tackle Trent Williams returned to practice after suffering a neck stinger in Week 3 against the Arizona Cardinals. That's good news... -
Kyle Shanahan explains why two key 49ers can miss practice and still play vs. Broncos
Two key San Francisco 49ers defenders haven't practiced this week, but head coach Kyle Shanahan doesn't seem concerned about their availability for Sunday's game against the Denver Broncos. Linebacker Dre Greenlaw is dealing with a quadriceps injury, while defensive end Keion... -
49ers FB Kyle Juszczyk avoids long-term injury, expected to miss 2-3 weeks
On Monday morning, ESPN's Adam Schefter reported that San Francisco 49ers fullback Kyle Juszczyk could miss "a couple of weeks" after suffering a knee injury in Sunday's win over the Denver Broncos. However, Juszczyk and the 49ers were awaiting MRI results to determine the...