There are a couple of recent (post-Bills game) threads that indirectly touch on this, but between the next two Eagles games vs San Francisco and at Dallas, the 49ers game is the much more important one of the two.

Oversimplifying things, the Eagles will probably win the tiebreaker with the 49ers if they beat them (obviously they’d win a 2-way tiebreaker, though a 3-way tie between the Eagles, 49ers, and Lions would be problematic) but almost definitely lose any 2 or 3-way tiebreaker between themselves and San Francisco if they lose. By contrast, if the Eagles lose to Dallas, there’s still a good chance they would win a tiebreaker against the Cowboys, especially if they tie at 14-3.

To further explain this, here’s the tiebreaker order for ties within a division and within a conference:

DIVISION TIEBREAKER ORDER

1. Head-to-head record
2. Division record
3. Common opponents record (12 common games excluding games against one another in 2-way ties)
4. Conference record (12 conference games)
5. Strength of victory (i.e. total number of wins by all the teams a particular team has beaten)

CONFERENCE TIEBREAKER ORDER

1. Head-to-head record if applicable
2. Conference record (12 conference games)
3. Common opponents record (4 game minimum threshold)

In the case of an Eagles loss to the 49ers, the Eagles would only be one game ahead in the standings (10-2 vs 9-3) and would lose the 2-way, head-to-head tiebreaker with the 49ers. They’d also lose all 3-way tiebreakers with the 49ers that also involve Detroit because the 49ers would be guaranteed to finish with a better conference record than the Eagles (and possibly also the Lions). The Eagles have already played all of their non-conference games (4-1 in those games), and are currently 6-0 in conference games. By contrast, the 49ers have already lost 2 of the 4 played non-conference games. Regardless if the Eagles, 49ers, and Lions tied at 14-3, 13-4, etc., San Francisco would be guaranteed to finish with a better record vs the NFC than the Eagles. (Detroit, who is currently 3-1 in their non-conference games and like San Francisco has one non-conference game remaining, could also finish ahead of the Eagles, tied with the 49ers in the NFC record tiebreaker, or finish tied with the Eagles but behind the 49ers.)

By contrast, an Eagles win over the 49ers would put the Eagles 3 games ahead of the 49ers in the standings (11-1 vs 8-4) with only 5 games remaining. They’d win any 2-way tiebreaker with San Francisco. They’d still lose a 3-way tiebreaker with the San Francisco that also includes Detroit because 1) the Lions did not play either the Eagles or 49ers (negating the Eagles win over the 49ers) and 2) the 49ers would win the conference record tiebreaker at 13-4, 12-5, etc. for the reasons discussed above. Having said that, keep in mind the Eagles would also need to finish 2-3 in their final 5 games for a 3-way tiebreaker to come into play.

Switching to the Eagles vs Cowboys tiebreaker, in contrast to the 49ers tiebreaker where the Eagles only win a 2-way tiebreaker with San Francisco if they beat them (and are in trouble if a 3-way tiebreaker comes into play, win or lose), the Eagles have a good chance of winning many tiebreaker scenarios with Dallas even if they lose to the Cowboys on December 10th. That’s especially true if the Eagles sweep the Giants in their two remaining games against New York. The key factor here is Dallas has already lost 3 conference games (at ARI, at SF, at PHI) while the Eagles have not yet lost any. As long as the Eagles sweep the Giants, the Eagles will win ANY tiebreaker with the Cowboys at 14-3 even if they lose to Dallas on 12/10 (i.e. the Eagles can afford to lose one of the following three games - vs SF, at SEA, vs ARI - in addition to losing the 12/10 game to Dallas). Additionally, assuming the Eagles sweep the Giants, the Eagles have a good chance of winning the tiebreaker with Dallas at 13-4 if the Cowboys lose to any team remaining on their schedule besides Detroit (Dallas could win the common opponents tiebreaker vs the Eagles in that scenario, due to the Lions being a non-common opponent for the Eagles and Cowboys and the Eagles finishing 3-0 against their non-common opponents - TB, MIN, KC).

TL:DR version: The Eagles cannot beat the 49ers in a 2-way tiebreaker if they lose to San Francisco, but would win a 2-way tiebreaker if they beat 49ers on Sunday (though a 3-way tiebreaker also including Detroit would be problematic in either scenario). By contrast, the Eagles have a good chance of winning a 2-way tiebreaker with the Cowboys even if they lose to Dallas on Sunday 12/10. There’s a good chance that’s true if the Eagles sweep the Giants, and definitely true if they sweep the Giants and win at least 2 of their other 3 remaining games (vs SF, at SEA, vs ARI).