It's not just injuries to blame for 49ers' slow start

San Francisco suffered three more significant injuries in the loss to the Cardinals. First, kicker Jake Moody suffered an ankle injury, and the 49ers moved quickly, signing veteran kicker Matthew Wright to temporarily replace him. 

Second, rotational defensive end Yetur Gross-Matos, who played in three of the team's five games, suffered a knee injury that required surgery.

Lastly, San Francisco's secondary also took a hit as starting safety Talanoa Hufanga, who returned from a torn ACL injury last month, will miss at least a month with torn ligaments in his wrist.

In McCaffrey's absence, RB Jordan Mason has filled in ably, leading the team with 536 rushing yards and three touchdowns and averaging 5.1 yards per carry. He has also factored into the 49ers' passing attack, with seven receptions for 66 yards. 

Mason's performance has impressed his teammates. In fact, All-Pro offensive tackle Trent Williams recently commented that Mason reminds him of Marshawn Lynch.

Thus, while McCaffrey's unavailability is not ideal, it alone has not had outcome-altering consequences for San Francisco.

So, what is the explanation for the team's shaky start?

Some 49ers players and observers have found fault with defensive coordinator Nick Sorensen. After the loss to the Cardinals, star defensive end Nick Bosa criticized Sorenson for not making adequate in-game adjustments. Similarly, 49ers beat reporters have noted that the defense is trending down, ranking 20th in the NFL in yards yielded per play to opponents and surrendering first downs to opponents on 43.3% of third-down plays.

San Francisco's only two wins have come in contests with the New York Jets and the New England Patriots, neither of whom are setting the world on fire, as evidenced by the former team's firing of its head coach and the latter's replacement of its starting quarterback.

All is not well with the reigning NFC champs, and the questions will only get louder if they do not deliver a victory on Thursday evening in Seattle.