At 6-8, the best the Dolphins can do is 8-8, which means they could do no better than the No. 6 seed because Indianapolis, in second place in the AFC South, already has nine victories.
Miami's only hope is to tie for the sixth-best record in the AFC and emerge based on winning the tiebreakers.
Before explaining how the playoff tiebreaker scenarios would come into play, let us simply state everything that has to happen for the Dolphins to get into the playoffs:
1) The Dolphins have to beat both Buffalo and New England.
2) The New York Jets have to lose one of their last two games, either next Sunday at home against San Diego or Dec. 30 at Buffalo.
3) The Pittsburgh Steelers have to beat the Cincinnati Bengals this Sunday.
4) Cincinnati also has to lose at home against Baltimore on Dec. 30.
5. Pittsburgh has to lose at home against Cleveland on Dec. 30.
If all of those five things happen, the Dolphins, Bengals and Steelers would finish at 8-8.
The first step in a three-way tie involving two teams from the same division is to eliminate one team from that division. In this case, Cincinnati would be eliminated because they would have been swept by the Steelers.
That would leave the Steelers and Dolphins involved in a tiebreaker.
Tiebreaker No. 1 is head-to-head competition, but the teams didn't face each other, so it doesn't apply.
Tiebreaker No. 2 is record vs. common opponents, with a mininum of four games. The common opponents for the Dolphins and Steelers this season were the Jets, Cincinnati, Oakland and Tennessee. The Dolphins are 3-2 against those teams (split against the Jets, beat Oakland and Cincinnati, lost against Tennessee); the Steelers would be 3-2 (sweep against Cincinnati, beat the Jets, lost against Oakland and Tennessee).
That would move things to tiebreaker No. 3, which is conference record. Under the scenario that would leave the Dolphins and Steelers at 8-8 fighting for the last playoff spot, the Dolphins would be 6-6 in conference play, while the Steelers would be 5-7.
And that's how the Dolphins would earn the last playoff spot.
In case you're wondering why the Jets have to lose and therefore not be involved in a tie with the Dolphins for the last playoff spot, remember the rule that dictates division tiebreaker be applied first.
If the Jets and Dolphins both finish 8-8, New York would get the tiebreaker nod by virtue of a better record (7-7 vs. 6-8) against common opponents.