The San Francisco 49ers’ task all season was clear. Score, score and score again on offense, because the young defense was going to need a safety net. And, for many weeks, that’s exactly what they did.

But on Saturday night, that all came to a screeching halt, along with the 49ers’ hopes of a first-round bye and a comfy home-field advantage possibly all the way to the Super Bowl. The 13-3 loss to Seattle was a tale of defenses: The Seahawks were exceptional and the 49ers weren’t nearly good enough. One defense looked Super Bowl-ready. One did not.

In a prime time game, six days after a wild offensive shootout, we saw what happened when the 49ers’ offense was smothered. The outcome was what was foreshadowed in the offseason with the exodus of defensive veterans. And again in the first weeks of the season when defensive stars Nick Bosa and Fred Warner were lost for the season to injury.

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In the disappointing aftermath of the loss, there was a lot of praise that the defense held Seattle to just 13 points. But let’s be honest: The low output was largely due to self-inflicted damage by the Seahawks. They missed two very makeable field goals and on the first drive of the game, marched downfield but came away empty because of baffling playcalling at first-and-goal from the one. If things had bounced just a bit differently, Seattle might have put the 49ers in a three-score hole early.