The 49ers’ secondary is getting a shakeup at just the right time for Malik Mustapha.
With Marques Sigle sidelined by a high-ankle sprain from Sunday’s 24-14 win over the Denver Broncos, San Francisco will roll into its Week 5 matchup with the Seattle Seahawks with a different starting safety pairing. The good news for the 49ers is that the next man up is one they trust.
Mustapha is poised to step in for Sigle after spending the first four weeks of the season in a rotational role. Injuries during training camp knocked him out of the starting picture, but he never disappeared from the defense. Even with Sigle and Ji’Ayir Brown holding down the starting jobs, Mustapha has been active in the rotation and has logged 49 defensive snaps this season.
His latest outing against Denver was his busiest yet, with 21 defensive snaps, and he made one of the biggest plays of the game. Early in the second quarter, with the Broncos threatening in San Francisco territory on their penultimate drive before halftime, Mustapha read Bo Nix perfectly, drove on the ball and got in front of Evan Engram to break up the pass with a diving deflection. It was his first pass breakup of the season, and it helped keep Denver from adding to a 3-0 lead.
The play showed exactly why the 49ers value him: instincts in coverage, closing speed and the kind of physical edge that fits what they want at safety.
Head coach Kyle Shanahan made it clear Monday that he’s been impressed with what he’s seen from Mustapha, especially as the safety gets healthier and settles back into rhythm.
“Yeah, definitely. Malik just had some unfortunate injuries during training camp, so he got a late start, but got his first practice out there in Australia and I think he’s been awesome this whole month.
That’s why we’ve been mixing him in there more regardless, even with all those guys healthy. We started mixing him in last week trying to get him some series and stuff.
Every time he’s come in, I think he’s played at a high level. I thought he did that yesterday and made one of the biggest plays in the game yesterday on that third-and-five when he broke that pass up.
I’m real excited with Malik and how he’s looked.”
Shanahan also praised Sigle’s start to his second season before the injury hit. The fifth-round pick from last year has been steady in both the run and pass game, according to his coach, and has played faster and with more confidence.
“I think he’s been playing his ass off in the run and pass game. The way he’s filled on some of these tackles, just how solid he’s hit people and how quickly he’s done it getting up in there.
I thought he’s done it good in the pass game too. He did a lot of good stuff last year, but I think he has taken it to another level, just playing a little bit faster, hesitating less, knowing what he’s doing and really playing well before that injury.”
Sigle is expected to miss several weeks, which opens the door for Mustapha to make a real case for himself in the lineup. He’ll also carry a little extra comfort into Seattle. His first career interception came in the 49ers’ 2024 win over the Seahawks, and San Francisco is trying to keep the good times rolling there with a fifth straight regular-season road win over Seattle.
If Mustapha can keep building on the flashes he’s shown, the 49ers could be in position to move to 5-0 and grab their third division win of the season while tightening their grip on the NFC West.
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