All the most important games of Week 17 are being played in the NFC as the seeding in that conference is still wide open. By contrast, the AFC seeding picture is relatively more determined at this point, with the #1 seed locked up and the #4 seed all but.
1. Being played for the unofficial (but non-arbitrary!) title of NFL Champion.
2. Both teams are in the top half of the NFL, by Mike Beouy's ranking, which, in turn, is extrapolated from the weekly betting lines for each game. "#1" means that this game features the highest minimum ranking of both teams playing [i.e. the ranking of the lower-ranked team].
3. The point spread on this game is 1.5 or lower, which translates into winning odds of about 55% or under for the favored team. Spreads this low are fairly uncommon. For comparison, homefield advantage is generally worth about 2.5-3 points.
4. Has the largest effect on any one team's playoff chances, by the same calculation used to determine games' overall importance—with one difference: while this calculation is generally based on the Vegas odds for each game, from the POV of a team that's actually involved in the game, its odds are considered 50-50 no matter what, since this game's results are "in its control".
5. Has the highest minimum effect on the chances of either team involved. As in the previous case, for this purpose, each team's odds of winning its own game are considered 50-50 from its POV.
6. Has an impact [in case the rankings are derived from a Monte Carlo simulation: a statistically significant impact]on the highest number of teams in the NFL.
7. Highest impact on which teams make the playoffs at all, without taking seeding into account.
8. Highest impact on the postseason with seeding taken into account, giving each seed a weight proportionate to its theoretical correlation with Super Bowl victory (accounting for home field advantage but neglecting team strength) as calculated by Brian Burke of advancedfootballanalytics.com (via Mike Beuoy).
Games of Week 17, Ranked by Influence on Super Bowl Picture1
Games of the Week
TITLE GAME/MOST IMPORTANT GAME OF THE WEEK BY “ABSOLUTE IMPORTANCE”/RELEVANT TO MOST TEAMS/MATTERS MOST TO ANY SINGLE TEAM
This week the Saint Louis Rams try to seize back the title that they lost to the Cardinals two weeks (and, for the Cardinals, quarterbacks) ago. Trying to do so against this amazing punt return that the Seattle Seahawks official website brings you in all its inglory—so you would not by any means be crazy for thinking Saint Louis has a chance.
On the other hand, Saint Louis pulled out all the stops to win that last game against Seattle—besides the aforementioned punt return, it also included a shockingly bold fake punt to seal the game, and one has to wonder if Jeff Fisher has anything left in his bag of tricks. Additionally, for them a victory is simply a matter of pride, whereas for Seattle, this game is more important than any other game this week is to any other team: if they win it, they’re guaranteed the top seed, whereas if they lose it, they tumble at least to 3rd, and possibly even to 5th (or, in a very unlikely scenario where Detroit ties Green Bay, 6th). Perhaps it’s in part for these reasons that Vegas has made the Rams 12.5 point underdogs for this game.
Those heavily one-sided odds are the only thing preventing this from being Game of the Week, as, if odds were not considered, this would actually edge out Detroit-Green Bay as the most important game of the week. What makes this so important is, primarily, its impact on the top couple of seeds. A Seattle win guarantees Seattle a top Seed, with the second seed belonging to Detroit or Green Bay (or, if those two tie, Dallas), while a Saint Louis win bumps Seattle all the way down to third place, at least, thus affecting both of the top two seeds. The top two seeds, in turn, are extremely important because they are worth one whole playoff victory each (the bye week), which is the main reason this game is so important.
Another factor in its importance is that it’s the game that affects the most teams, as all 5 of the non-NFC-South teams contending for the various seeds have an interest in it. (Arizona-San Francisco can technically say the same, but Green Bay’s stake in that game is limited to the case where Green Bay draws its own game with Detroit, which is so unlikely as to be relatively negligible.)
Its expected importance, however, factoring in the relatively small chance of an upset, is somewhat less, so the actual game of the week is:
MOST IMPORTANT GAME OF THE WEEK (“EXPECTED IMPORTANCE”)
The Detroit Lions taking on the Green Bay Packers in a battle for supremacy over the NFC North at the least, and, if Seattle falters, the entire NFC. The winner of this game gets a bye at the least, and, if Seattle loses, even the top seed. The loser, unless Seattle loses, plummets all the way to the sixth seed. The stakes could hardly be higher. Even without taking odds into account, this game would run a close second in importance to Seattle-Saint Louis. With Green Bay, though strongly favored, not nearly as heavy a favorite as Seattle in this game, it’s the most important game in the league in expected importance, hands down.
MOST IMPORTANT TO PLAYOFF FIELD
This is all when we consider weighted importance, accounting for the value of the various seeds. On the other hand, another reasonable way to look at the regular season is to consider a successful outcome making the post-season at all. If anyone views this season that way, it is surely the hapless teams of the NFC South—which makes it rather fitting that by this metric, the most important game of the week is being played between the Carolina Panthers and the Atlanta Falcons. Playing each other makes Carolina’s half-game lead nearly irrelevant here (it only comes into play in the very unlikely case of a tie), so there’s little to elaborate on here: it’s a simple case of “winner plays”, giving this game 100% importance as far as making the playoffs are concerned. Atlanta’s being slightly favored brings its expected value down a little, but only a very little, to 96%. The relative unimportance of the 4th seed brings this down to third-most-important game of the day in weighted importance, but even there, it is well ahead of the next most important games of the day.
MOST IMPORTANT AFC GAME (1:00 GAME)/CLOSEST MATCHED
The most important game in the AFC (hence the most important 1:00 game) is San Diego vs. Kansas City. The importance of this game lies in its bearing on the sixth seed. As this seed is currently controlled by San Diego, this game is relevant to all 4 contenders for that seed. Kansas City is one of these, which makes this a must-win for San Diego. It’s obviously important to Kansas City as well, who needs to win it for a chance at the playoffs, but even with a win, KC will need considerable help to get in, as Baltimore and Houston are in line ahead of it.
Currently, this game edges out Cincinnati-Pittsburgh by a hair (though that may change by tonight, depending on what happens in today’s games) in expected importance. In absolute importance, it’s just the opposite: Cincinnati-Pittsburgh has the slightest of edges there. The difference-maker is the line in each game: while both are expected to be close games, the spread in SD-KC is currently set at the extremely low 1.5 points, which means that Vegas expects it to be a really close game.
It’s also a high-level game: these are both good teams—and while they are also both prone to erratic performances, both of them know that it’s win-or-go-home this time, so expect them to be playing at their best. All in all, this should be an exciting one.