Why the 49ers Will Beat the Seahawks in Week 18

No one could've foreseen the San Francisco 49ers having the opportunity to clinch the No. 1 NFC playoff seed.

It felt impossible that it could happen from the moment Nick Bosa and Fred Warner went down for the season. Not to mention being without several other crucial players for a stretch of the season.

Yet, the 49ers can clinch the No. 1 seed in Week 18 on Saturday night against the Seattle Seahawks. To be in this position is nothing short of phenomenal. The 49ers could've easily folded, but they didn't.

They're currently riding a six-game winning streak with 12 wins on the season. The momentum is at an all-time high for the 49ers, and that is exactly why they will beat the Seahawks.

The 49ers have been an unstoppable force

Dec 28, 2025; Santa Clara, California, USA; San Francisco 49ers running back Christian McCaffrey (23) runs for a touchdown against the Chicago Bears in the first half at Levi's Stadium. Mandatory Credit: Sergio Estrada-Imagn Images | Sergio Estrada-Imagn Images

Momentum is everything in the NFL. It's about getting hot at the right time, which is what the 49ers are doing. Their offense has been stupendous during their six-game winning streak.

It starts with Brock Purdy. He had all the pressure in the world stepping back in as the starter after being out with a turf toe injury. The 49ers' offense looked strong with Mac Jones filling in.

But Purdy proved it can get stronger and go further with him. He's been sensational, minus a first-half debacle against the Carolina Panthers. Purdy is a reason the 49ers have so much momentum.

So is Christian McCaffrey. The run blocking has finally found its groove, and McCaffrey is thriving with it. He seems to have found the missing gear he left in 2023 when he was the Offensive Player of the Year.

And let's not forget about George Kittle. You could make the case that he looks better than he ever has in his career this season. Now, he will be hobbled if active against the Seahawks, but it's better than nothing.

The 49ers' offense is soaring high, and there's little reason to believe they'll be completely silenced. Even with their turnstile defense, they've managed to overcome them.

What Seattle's undoing will be

Dec 28, 2025; Charlotte, North Carolina, USA; Seattle Seahawks quarterback Sam Darnold (14) looks to throw a pass while scrambling against the Carolina Panthers during the fourth quarter at Bank of America Stadium. Mandatory Credit: Jim Dedmon-Imagn Images | Jim Dedmon-Imagn Images

Ultimately, what will be the reason the 49ers beat the Seahawks is the stark difference between the two starting quarterbacks. It's Sam Darnold the pumpkin versus red hot Purdy.

Of course, one quarterback has a significantly tougher defense to go against. Seahawks coach Mike Macdonald has discombobulated Purdy before, and it could happen again on Saturday night.

But the pressure of this game is insanely high. Purdy will not fold to that pressure. He's played in plenty of high-pressure games like Saturday night before and been fine.

Darnold, on the other hand, has demonstrated to crumble like a cookie. He hasn't been playing that well recently either. Maybe the 49ers' defense is the chance for him to course correct.

However, it is in these playoff moments that a quarterback can crack against anyone. They're not just facing the opposing defense; they're facing themselves.

I fully expect Darnold to fold, especially if the game is close in the end. Robert Saleh should be able to confuse Darnold enough to keep him timid.

The 49ers have all the momentum in the world. They are the home team and know how to handle these games. Seattle doesn't, especially Darnold.

I like the team that has been performing well with the odds stacked against him this year.

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The 49ers have been an unstoppable force

What Seattle's undoing will be

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