College football is like dominoes. One play goes right, and a team finds itself in the Playoff. One goes wrong, and a coach is fired.

With the exception of Alabama, which lapped its conference, this year’s Playoff teams all got there in part because things went just barely right in critical situations. Others missed out because things went just barely wrong, even if they didn’t know it at the time. Elsewhere, surprising twists thrusted legacy programs into course-altering coaching changes. (And plenty of things we thought mattered a lot, like Tennessee’s many September comebacks or Texas’ win over Notre Dame, ultimately didn’t.)

These are the moments that changed how 2016 unfolded.

Week 2: Penn State throws an interception in the end zone at Pitt.

Both teams were unranked entering a long-awaited rivalry renewal. Pitt jumped to a 28-7 lead in the first half, but Penn State cut its deficit to 42-39. The Nittany Lions were driving in the final two minutes, poised to complete a comeback.

Trace McSorley’s 32-yard heave into Pitt’s end zone fell into the arms of defensive back Ryan Lewis.

It was Penn State’s first loss, and the Nittany Lions would only lose one more time. It’s the simplest reason the Big Ten champions missed the Playoff.

Week 4: Adoree’ Jackson falls down.

USC fell to 1-3. The Trojans haven’t lost since. If they’d won here and everything unfolded as it did afterward, they’d have played Washington in the Pac-12 title game. Think that might have been a little dangerous for UW?

Also Week 4: Les Miles literally runs out of time.

Remember this utter chaos?

LSU’s last play was gorgeous. It also happened after the clock read zeroes and didn’t count. Miles lost his job the next day. This guy took it from there:

Also Week 4: Washington comes up with an overtime stop in Tucson.

Arizona was on its way to a 3-9 season. Washington, then ranked No. 9, eventually got to the Playoff. That wouldn’t have happened with a loss to Zona, and the Huskies’ defense averted crisis. Washington’s escape also snapped a bit of desert futility:

No matter how good or bad [Arizona State or Arizona is], playing on the road in Arizona always seems to be a bizarre experience for the Huskies where nothing seems to go your way. The Huskies hadn’t won in the desert since 2006, so getting this win, even if it was ugly, was a milestone for the program.

Clemson interjection: Weeks 1, 2, 5, 7, and 8

The Tigers finished with one loss, to Pitt in November. If they’d gotten another, they’d have almost certainly missed the Playoff.

Clemson’s first game, at Auburn shouldn’t have been close. But Dabo Swinney messed up, and Auburn got a shot to win.

This chaos, which resulted in a Clemson touchdown (as opposed to a Troy touchdown) the very next play. Clemson won by six.

This Louisville receiver went out of bounds a yard short of the line to gain in the last minute of a game, maybe because someone didn’t lay out an orange marker correctly. Change this one move, and Louisville’s in the ACC Championship.

This NC State kicker missing a 33-yard field goal:

This low but probably legal FSU block being penalized, nullifying a fourth-quarter Dalvin Cook burst while FSU led Clemson in late October:

Hoo boy, was Jimbo Fisher upset:

"It was ridiculous," Fisher said. "It was not a chop. It was a not chop. I will tell you what: you hold coaches accountable, you hold players accountable; hold the damn officials accountable. It is garbage, and then to call another penalty on the sideline is even more garbage. It's cowardly, gutless, and wrong.”

Clemson might have still won even without the call, but would’ve been in bad shape.

Week 8: A block six turns the Big Ten East race on its head.

It changed the Big Ten Championship, if not the Playoff.

Week 12: Texas throws an overtime interception at Kansas.

Kansas hadn’t won an FBS game in two years. Charlie Strong was officially out of his job eight days later. Tom Herman replaced him, and Strong went to USF.

We’ll never know if Texas would’ve fired a 6-6, bowl-eligible Strong. But once Kansas happened, Strong knew what was up.

The most painful part of the Strong post game presser.



"Do you know what this means for your future?" pic.twitter.com/MRNuTko8au — Casey Keirnan (@CaseyKeirnan) November 20, 2016

Strong and Miles weren’t the only coaches to get fired, but they were the two biggest names, and the timing of their firings can both directly be tied to specific plays.

Week 13: Ohio State gets the Spot Heard ‘Round the World.

This one happened late enough in the season and in a big enough game that it was obvious it’d change everything, but it still has to be here. Michigan and Ohio State fans might never stop tweeting each other screenshots from it.

Our Ohio State blog turned this into a T-shirt.

Everyone who’s in the Playoff almost wasn’t, except for Bama. USC and Penn State almost had the juice, and maybe LSU and Texas almost didn’t fire their coaches. There’s a lot we’ll never know, because there are no mulligans here.