Three Plays That Heavily Influenced the 49ers' Loss to the Seahawks

Losing 13-3 to the Seattle Seahawks meant that the San Francisco 49ers needed at least a few plays to pan out differently.

If they did, they probably would win the game and become the No. 1 seed in the NFC. Here are the three plays that heavily influenced the 49ers' loss to the Seahawks.

Ji'Ayir Brown and Malik Mustapha blunder

Points came at a premium in this game, which meant touchdowns were a gold mine. There was only one touchdown scored in this game, and it was by the Seahawks.

However, it was a touchdown that the 49ers' defense shouldn't have allowed. At the 4:37 minute mark of the first quarter, the Seahawks were faced with a 3rd-and-2 at the 49ers' 27-yard line.

All the 49ers had to do was get a stop, and they would force Seattle to kick a field goal. Unfortunately, Ji'Ayir Brown and Malik Mustapha had other ideas. They allowed running back Zach Charbonnet to take it to the house on his run.

Brown got easily erased by backup tight end and former 49er Eric Saubert. It was a pitiful effort on Brown's part. Mustapha would one-up that by completely whiffing a tackle on Charbonnet.

That touchdown allowed gave the Seahawks a significant advantage throughout the game, and it was all because Brown and Mustapha were awful on the play.

Hail Mary run play

Jan 3, 2026; Santa Clara, California, USA; Seattle Seahawks running back Kenneth Walker III (9) rushes the ball against San Francisco 49ers cornerback Upton Stout (20) during the first half at Levi's Stadium. Mandatory Credit: Sergio Estrada-Imagn Images | Sergio Estrada-Imagn Images

Arguably, the dagger play of the game against the 49ers came in the third quarter at the 3:48 minute mark. Seattle was faced with a 3rd-and-17 at their own 25-yard line.

The 49ers' defense had them right where they wanted them. They were about to force a three-and-out and swing momentum back to their side.

And then, the 49ers' defense forgot how to tackle. Running back Kenneth Walker converted a first down by taking a handoff for 19 yards.

The 49ers had their shots at Walker, and the Seahawks running it was essentially waving the white flag. Yet, somehow, they converted it. The drive would finish with a field goal to increase Seattle's lead to 13-3.

Christian McCaffrey coughs it up

Christian McCaffrey is supposed to be the star player that the 49ers look to when they are in a pinch. He had a prime opportunity to be the hero in the fourth quarter at the 10:27 minute mark.

The 49ers' offense was marching down for the first time all game. A touchdown was within reach for them to get the game back within a score and put pressure on Seattle.

They made it all the way to Seattle's six-yard line. Brock Purdy dropped back to pass and hit McCaffrey, but he couldn't secure the catch and bobbled it, turning it into an interception.

Once that happened, the 49ers were cooked. They wouldn't get the ball back until the final few minutes of the game. Just a disappointing outing for McCaffrey and the 49ers' offense.

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Ji'Ayir Brown and Malik Mustapha blunder

Hail Mary run play

Christian McCaffrey coughs it up

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