The San Francisco 49ers enter Week 18 with one easy playoff seeding scenario: they’re the No. 1 seed if they win their final game. But what happens if their six-game win streak is snapped at home Saturday night?

While fans may not want to consider the possibility of a defeat at the hands of the Seattle Seahawks at Levi’s Stadium, it’s worth exploring what happens should the 49ers fall, where they’d wind up seeded and what teams they could play in the first round if they miss out on the bye week.

Here are the seeding scenarios and potential playoff matchups awaiting the 49ers after Week 18:

How the 49ers get the No. 1 seedWho is the 49ers playoff opponent if they’re the No. 1 seed?

This is tough to answer since there is no certainty just yet. San Francisco would secure a bye week on wild card weekend should they get the top seed. After that they’d be in line to host the lowest-remaining seed, which could very well be either the No. 5 or No. 6 seed which would be one of the Los Angeles Rams or Seahawks.

How the 49ers get the No. 5 seed

Two things would have to happen here, and it requires San Francisco to get some help by way of the division record tiebreaker. If the Rams beat the Cardinals, they’ll have the same division record as the 49ers. That would move the next tiebreaker to record against common opponents where LA has a sizable advantage. If LA falls to the Cardinals, they’ll finish with a worse division record than the 49ers, giving San Francisco the tiebreaking edge.

49ers lose to SeahawksRams lose to CardinalsWho is the 49ers playoff opponent if they’re the No. 5 seed?

Securing the No. 5 seed would be preferable for matchup purposes if they’re not getting the top spot. They’d have to go on the road for wild card weekend, but their opponent would be dependent on the outcome of Saturday afternoon’s game between the Tampa Bay Buccaneers and Carolina Panthers.

Panthers win Week 18: 49ers at PanthersBuccaneers win Week 18: 49ers at BuccaneersPanthers-Buccaneers tie Week 18: 49ers at PanthersHow the 49ers get the No. 6 seed

This is the worst-case scenario for San Francisco, but it’s probably likelier than the No. 5 seed.

49ers lose to SeahawksRams beat OR tie CardinalsWho is the 49ers playoff opponent if they’re the No. 6 seed?

Where the 49ers would go for their wild card game depends on how things shake out for the Chicago Bears and Philadelphia Eagles in their respective season finales. Chicago is currently the No. 2 seed and on track to host the No. 7 seed Green Bay Packers. Philadelphia has the same record as Chicago, but the Bears beat them head-to-head and hold that tiebreaker.

Bears win Week 18: 49ers at EaglesBears lose and Eagles lose in Week 18: 49ers at EaglesBears lose and Eagles win or tie in Week 18: 49ers at Bears

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