The 49ers must flip the script without franchise quarterback Jimmy Garoppolo — and it starts on defense.
There’s perhaps no more important player to San Francisco on that side of the ball than promising second-year pro Reuben Foster, who played like one of the NFL’s best young linebackers as a rookie in 2017.
But that wasn’t the case in Kansas City, when Foster’s struggles in his first game back from suspension exacerbated the defense’s inability to slow the Chiefs. Foster, normally the team’s most reliable tackler, missed six in the game, one more than the five tackles he made.
And the 49ers allowed touchdowns on all five first-half possessions, yielding 35 points at the break, effectively putting the game out of reach with 30 minutes to play.
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“I don’t take it lightly on myself. That’s uncalled for,” Foster said of his performance.
Foster acknowledged leading up to the game that it was going to be important to rein in his excitement. He was sorely missed during the first two weeks while suspended, when San Francisco lost by one possession in Minnesota and barely hung on to beat Detroit, all while the Vikings and Lions took advantage of Foster’s backups, Brock Coyle and then Elijah Lee after Coyle got hurt in the opener.
Cornerback Richard Sherman watched the second half from the sideline in Kansas City after leaving with a left calf strain. The defense rebounded and allowed just three points to the Chiefs after halftime, and Sherman noted that San Francisco’s first-half problems could be resolved quickly.
“It’s bad angles, lunging, diving, not running through people. It’s just, all things can be fixed in a second,” Sherman said. “It could be fixed in games if guys just took a few more steps.
“With Reub, it’s his first game back. Any time it’s your first game back, you’re going to have some growing pains. I think guys are getting it fixed and the coaching staff is doing everything in practice to make sure guys are practicing better.”
There was plenty of buzz surrounding San Francisco’s linebackers last week. Rookie third-round pick Fred Warner played exceedingly well in those first two games with Foster away from the team. Sunday was Warner and Foster’s first game together as the starting duo, which the team envisions will be the centerpiece of its defense for years to come.
“It felt amazing just playing with (Warner),” Foster said. “People call him a young buck, but really he’s just like a vet out there.”
But Foster and Warner missed 10 tackles combined, according to Pro Football Focus, while San Francisco missed 17 on the day. The 49ers enter Sunday’s game against the Chargers with more missed tackles than any team in the NFL, according to the scouting service.
“You can see it with your own eyes just watching the game. We have to tackle better in order to improve,” coach Kyle Shanahan said. “In this last week, I thought we had too many mistakes versus a good offense that gave them too many freebies in that first half, which put us in a huge hole.”
Missed tackles were also a problem against the Vikings and Lions. Defensive coordinator Robert Saleh stressed last week that players tracking ballcarriers at the wrong angle was the leading culprit. Against the Chiefs, defenders were losing track of their fundamentals.
“It’s very clear when you turn on the tape that we’re actually lunging and ducking our heads at the point of attack,” Saleh said. “When you teach tackling, everything that we talk about is you’ve got to run your body through their body. Get a body on a body, step on their toes, wrap up, keep your feet moving, drive for five (yards) and get them to the ground.”
The 49ers will face another stiff test Sunday against the Chargers, who rank in the top 10 both passing and rushing offense. Quarterback Philip Rivers’ 115.7 passer rating through three games would be the best of his career over a full season. He’s thrown eight touchdowns to just one interception while San Francisco and Dallas are the NFL’s only two teams yet to make an interception this season.