​The Chargers Shouldn't Fire Mike McCoy (For His Goal-line Play-Calling)

San Diego Chargers fans want head coach Mike McCoy fired for his fourth-quarter play-calling, but they're way off base—at least about the play-calling part.

Down by one score with just under three minutes left on Sunday, the Chargers had a first-and-goal from the Denver Broncos' two-yard line. Chargers tailback Melvin Gordon had been punishing the Broncos all game; he'd finish with 23 carries for 111 yards (a 4.8 yards-per-carry average). Quarterback Philip Rivers had been under a constant barrage of pressure, picked off three times and sacked four times. And so it was that, two yards from paydirt, McCoy called four straight passes. All fell incomplete, and the Chargers blew an amazing chance to pull within one game of the Broncos (and clinch tiebreaker rights over them in the process).

McCoy flouted all traditional football wisdom with those calls, but his choices were hardly indefensible. Keith Goldner of NumberFire.com took a look at this for The MMQB in 2013 after Chip Kelly's Eagles ran, or more accurately, passed into a similar situation against the 49ers, and his analysis is illuminating.

Teams generally run far more often than they pass in that scenario, because that's the conventional wisdom and this is the NFL; also, Net Expected Points are higher running than passing. However, expected points are skewed by what might happen on a turnover; if a corner jumps a goal-line throw it's likely to be a pick six, but a goal-line fumble is very unlikely to be run back for a score.

So Goldner looked at Success Rate and TD Rate for running and passing for all goal-to-go situations since 2000. From the one-yard line, the numbers perfectly match conventional wisdom: NFL teams scored a touchdown on 53.9 percent of runs, and 48.3 percent of passes.

But move twice as far from paydirt and the odds change wildly: A two-yard pass has a 45.2 percent chance of finding a friendly pair of hands in the end zone, but a runner breaks the plane just 40 percent of the time. Given four downs from the two, though, it doesn't really matter whether you run or throw: Offenses almost always win. And given Goldner's TD rates, throwing four times from the two-yard line should result in at least one touchdown 90.98 percent of the time (per this binomial probability calculator).

To repeat: What Mike McCoy did in that situation works nine times out of ten. Sunday just happened to be McCoy and the Chargers encountering the dreaded tenth time.

Even so, it's not like McCoy decided on first-and-goal to throw four times. He evaluated each down and "called the plays [he] did," one at a time:

Mike McCoy on 4 passes from the 2:
"We called the plays we did."
Annnnnnnd scene. #SDvsDEN
— Derek Togerson (@DerekNBCSD) October 30, 2016

Moreover, half of play-calling is deception; when everyone in the stadium expects you to run, running is hardly a slam dunk. No matter how you slice it, McCoy shouldn't be fired for throwing four times from two yards out. Now, if pitchfork-wielding Chargers fans instead hollered that McCoy should be fired because his team has found new and spectacular ways to lose five of eight of what could be their last 16 games in town, they might have a point.