49ers Suffer Major Shock: Nick Bosa to Miss Several Weeks With Calf Injury

SAN FRANCISCO — The San Francisco 49ers have received some unwelcome news just ahead of a crucial Week 3 matchup. Defensive star Nick Bosa will not take the field against the Arizona Cardinals and is expected to miss several weeks while recovering from a calf injury.

The news was confirmed after Bosa experienced the issue during Thursday’s practice. According to reports from ESPN and NFL Network, the 49ers defensive end suffered a calf strain and will need time to recover. ESPN reported that Bosa is expected to miss “a few weeks.”

Head coach Kyle Shanahan later confirmed that Bosa would be sidelined for several weeks. When asked about a potential return timeline, Shanahan said the team could not provide an exact date but estimated that it would be a matter of several weeks. He also said Bosa was understandably disappointed by the situation but is expected to return.

A Significant Loss for San Francisco’s Defense

Bosa is not only one of the most recognizable players on the 49ers’ defense but also plays a crucial role in the team’s ability to pressure opposing quarterbacks.

Through the first two games of the 2026 season, Bosa had recorded seven tackles, two tackles for loss and one quarterback hit. His absence will therefore place additional pressure on San Francisco’s defensive line as the team prepares to face Arizona.

Notably, Bosa’s injury is not the only health concern affecting the 49ers’ defense.

Defensive tackle C.J. West has been placed on injured reserve because of a knee issue and is expected to undergo surgery. Sam Okuayinonu and Alfred Collins are also on injured reserve, while rookie defensive tackle James Thompson Jr. is reportedly expected to miss several weeks with an ankle injury.

The 49ers have also confirmed that rookie defensive end Romello Height will be unavailable against the Cardinals. As a result, the depth of San Francisco’s defense, particularly along the defensive line, has become one of the team’s biggest concerns heading into Week 3.

49ers Forced to Adjust Their Game Plan

Bosa’s absence will force San Francisco’s coaching staff to redistribute playing time and responsibilities among the remaining defensive players.

Bosa is routinely one of the players opposing offenses have to account for most carefully. Without him on the field, other defensive linemen will be asked to handle more snaps and find ways to compensate for the pass-rushing impact Bosa provides.

That will not be an easy task, especially with the 49ers already dealing with several health issues on defense.

Still, Shanahan has not indicated that the injury should be viewed as a long-term problem. The 49ers head coach emphasized that Bosa will return, but the team will need to monitor his recovery before determining a specific timetable.

Mike Evans Remains Questionable

While Bosa’s injury is a major concern for 49ers fans, the situation on offense is also worth watching.

Wide receiver Mike Evans is listed as questionable for the Cardinals game because of a hip issue. Evans missed the first two practices of the week but returned to practice on Friday.

San Francisco’s official injury report showed that Evans did not participate in practice on Wednesday or Thursday before returning Friday, while several other key players also appeared on the injury report.

That means the 49ers will have to wait until closer to kickoff to know exactly which players will be available.

Cardinals Matchup Draws Even More Attention

The 49ers are scheduled to host the Arizona Cardinals at Levi’s Stadium in their Week 3 matchup on Sunday, September 27, in the United States. San Francisco enters the game with a 2-0 record while dealing with a growing list of personnel questions because of injuries.

With Nick Bosa ruled out, attention will shift to the remaining defensive linemen and how Shanahan and his coaching staff choose to distribute the workload.

The biggest issue right now is that the 49ers have not provided a specific return date for Bosa. “A few weeks” is the timeframe Shanahan used to describe the current situation, but the actual recovery period will depend on how Bosa responds to treatment and rehabilitation.

For San Francisco, this is clearly a test of the team’s depth. The 49ers have opened the season on a positive note, but losing one of the most important players on their defense just before Week 3 will force the coaching staff to find an effective replacement strategy.

And with the NFL season still in its early stages, the biggest questions are not only how the 49ers will cope without Nick Bosa against Arizona, but also when the defensive star will be ready to return to the field.