Five reasons why 49ers are 5-0 and atop the NFL despite epic rash of injuries

The substation jokes haven’t stopped. And, still, the San Francisco 49ers can’t be stopped. What is going on here?

The 49ers are one of the NFL’s three undefeated teams, still unblemished despite all their annual injuries. This summer, their overall health was viewed among the biggest keys to the season. With an aging roster, and presumably less margin for error, they couldn’t afford so much attrition. So much for that.

They already have 16 players on injured reserve, a group that doesn’t include Nick Bosa, who has added to their only-in-Santa-Clara injury stories: The All-Pro pass rusher has missed the past three games after straining his calf while warming up.

The defensive line has been so decimated that unrecognizable names (Khalid Kareem, Ogbo Okoronkwo) are playing meaningful minutes. The wide receiver corps has been so compromised that they signed ex-draft bust Dante Pettis as practice-squad insurance (Pettis, of course, landed on injured reserve after one full practice).

Yes, the 49ers are beat up. And battering opponents. They whipped the Super Bowl-favorite Rams in Australia, toppled the defending Super Bowl-champion Seahawks in Seattle and own the NFL’s highest point differential (+61).

So, again, what is going on here? Here are the five biggest reasons they are 5-0.

A great quarterback

A great QB can mask a host of flaws. And I can hear the responses: Is Brock Purdy actually … great? Let’s answer with a statistic: With five more pass attempts, Purdy’s career pass rating (105.4) will qualify as the best in NFL history. That qualifies as better than very good.

Purdy outclassed Tom Brady in his first NFL start and was a league MVP candidate in his second season, but the 2026 version has been, well, should Joe Montana and Steve Young start making some room?

Purdy leads the NFL in passing touchdowns (13) and QBR (84.0), ranks fourth in yards per attempt (8.4) and completion percentage (69.0) and his pocket feel and scrambling ability were a major reason the 49ers became the first team in 21 years to not allow a sack in the season’s first four games.

Steve Young has talked about elite QBs reaching a career sweet spot when their Xs-and-Os knowledge allows them to toy with defenses. He has said that a problem for many is that once they reach that level of mental mastery, their physical skills have diminished. At 26, Purdy may not have achieved genius-QB status yet. But something is clearly clicking in his fifth season in Kyle Shanahan’s system.

“The game is so slow to him now,” linebacker Fred Warner/ said. “So he’s out there kind of just manipulating things.”

A Hall of Fame wide receiver

Speaking of greatness, Mike Evans has given the 49ers a desperately needed counter punch when facing Seattle’s great defense.

Last season, 49ers wide receivers combined for 83 yards in their two January losses to the Seahawks. Last Sunday, Evans had 75 receiving yards – on one possession, the 49ers’ had-to-have-it, second-half touchdown drive in their 32-29 win at Seattle.

Evans, 33, signed a bargain contract with the 49ers, eschewing more lucrative offers, because he was drawn to Shanahan’s offense. Just before Evans signed with the 49ers, he told his friend, former NFL running back LeSean McCoy, that he thought Shanahan’s system would allow him to run routes through wide open spaces.

McCoy agreed: “Mike’s going to get crazy, stupid busy,” he said on his podcast.

Evans arrived with Canton-worthy credentials, but, by some measurements, he’s never gotten this crazy, stupid busy in his 13-season career. Of Evans’ 24 catches (for 326 yards), 22 have resulted in first downs. His 91.7% first-down rate is a career high. And his 70.6% catch rate – he’s snagged 24 of 34 targets – would also be a career-best mark.

And he might only get better. Evans has grimaced through the past two games while playing with two broken ribs.

The defensive coordinator Shanahan always wanted

In January, the Cowboys hired Christian Parker as their defensive coordinator. Parker had no previous coordinator experience and now he requires assistance: Dallas hired longtime defensive coordinator Mike Pettine on Monday to give Parker a hand with the NFL’s 31st-ranked defense.

The polar opposite of Parker’s hiring: The 49ers’ addition of Raheem Morris. The three-time NFL head coach and Super Bowl-champion coordinator with the Rams has been so good that he’s made his well-regarded predecessor, Titans head coach Robert Saleh, look less impressive in comparison.

Morris is overseeing one of the NFL’s best defenses despite occasionally trotting out a spare-parts defensive line. With Bosa playing just two games, the 49ers rank third in the NFL in points allowed (18.6) and sixth in yards (297.2).

Morris, a safety at Hofstra, was a longtime NFL defensive backs coach, and he might have made his biggest impact in the secondary. The 49ers are still playing primarily zone, but Morris has introduced more match coverage, which allows zone defenders to closely attach to a receiver if a specific route is run.

The more aggressive style was a hit in training camp. Cornerback Renardo Green raised eyebrows by not-so-subtly taking a dig at Saleh while praising Morris.

“It’s easier to play faster,” Green said. “And I feel like he’s finer, more detailed with just realistic things. It’s a lot less thinking.”

Like many defenders, Green has raised eyebrows during the regular season. His three interceptions in five games are two more than he had in his first 31 career games, and one more than the 49ers cornerbacks had in 2025.

Kyle’s clicking, too

For starters, Shanahan’s presence made a huge impact before the season’s first snap: Evans and Morris, his close friend, probably wouldn’t be employed with the 49ers if he wasn’t the head coach.

But then there is also the matter of the job he’s done as the overseer of the NFL’s third-ranked scoring offense. Purdy has made it clear that his ongoing ascension is tied to Shanahan’s system and his increased understanding of its complexities. Shanahan told a Fox broadcast crew this season that Purdy is now starting to understand the “why” of his play calls.

And many of those play calls have deserved a “wow” this season. The most obvious: The hook-and-ladder, 80-yard touchdown against the Cardinals in Week 3. That 36-30 win was sealed when no defender was within 20 yards of tight end George Kittle on a 20-yard touchdown catch when Arizona was expecting a clock-draining, 2nd-and-10 run.

Shanahan is “probably the biggest weapon we have on offense,” Puni said.

Shanahan is also an obvious early season Coach of the Year candidate. He finished fifth last season and was second in 2022 and 2019.

The kids can play

The 49ers have enough All-Pros. This summer, it wasn’t clear whether their recent draft classes had produced enough reliable role players to assist their stars.

So far, the young supporting cast has included several rookies (running back Kaelon Black, defensive tackle Gracen Halton, pass rusher Romello Height, linebacker Jaden Dugger), 2025 picks who have taken a second-year leap (cornerback Upton Stout, guard Connor Colby, safety Marques Sigle) and established starters from the 2024 class who appear primed for career-best seasons (Green, guard Dominick Puni).

That group doesn’t include bad-intentions safety Malik Mustapha, a 2024 fourth-round pick who smashed Seahawks wide receivers throughout his debut 2026 start last Sunday. And it doesn’t include a 2025 undrafted free agent, defensive tackle Sebastian Valdez, who has provided solid snaps off the bench after toiling on the practice squad last season.

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This article originally published at Five reasons why 49ers are 5-0 and atop the NFL despite epic rash of injuries.