From then on, Atlanta did everything in their power to give the game away. Dallas opened the second half with two long touchdown drives (74 and 83 yards) in just over five minutes combined. Atlanta then scored a touchdown of their own and a field goal bringing the score to 39-24 with 7:57 left in the fourth quarter. The Cowboys then scored with three minutes left in the game, shrinking Atlanta's lead to nine points pending the PAT. What followed was one of the more surprising coaching decisions in recent memory. Conventional wisdom says the Cowboys kick the extra point, putting them down eight points with three minutes left and hope to get a stop and a chance to score a touchdown and tie the game with a two point conversion. The Cowboys instead took the road less travelled. They attempted the two point conversion following the touchdown and failed to convert, resulting in a nine point deficit with three minutes to go. What happened after has been talked about ad nauseam: Atlanta went three and out, the Cowboys marched 76 yards in just one minute and eight seconds, recovered an onside kick in the most ridiculous manner possible (Zuerlein used no kicking tee and the Falcons seemed to avoid the ball like it was a punt) and the Cowboys swiftly moved the ball into field goal territory, sealing the game as time expired. One of the main talking points after the game was of course the brutal collapse by the Falcons. But since this game involved the Cowboys, I would argue the most bandied about topic was the fact that the Cowboys chose to go for two after cutting the deficit to nine points. Many in the media lambasted the decision by Mike McCarthy, including noted NBC pundits Mike Florio and Chris Simms. I wanted to look at the decision and discuss both how unusual it was and how it was definitely the correct decision.
First, teams almost never behave as the Cowboys did when trailing by nine points. Since 1999, there have been 23 instances of a team cutting their deficit to nine with between eight and five minutes left (basically all situations similar to what Dallas faced on Sunday). In just three of those situations, the team elected to go for two: Carolina against the Rams in 2001, Buffalo against the Ravens in 2019, and Cleveland against the Ravens in 2019. So before 2019, in the timeframe where I have access to play-by-play data, a team elected to go for two just once. In all three of the cases, the team that elected to go for two lost the game. In the other 20 instances, when the team kicked the extra point, those teams won seven times and tied once, for a 0.375 win rate. To further highlight how unusual this decision was, since 1999 when a team scored a touchdown to trail by nine points at any point in the game, the team kicked the extra point 90.2 percent of the time (130 times out of 144).
But let's go back to the situation at hand. Given we only have three instances where a team went for two in a similar situation to Dallas, using the fact that none of them won the game does not hold merit (and that is without accounting for the fact that the Rams in 2001 and Ravens 2019 both went 14-2, thus proving to be a better-than-average opponent). Without a sufficient sample size where we can just analyze the results on the field, we have to turn to both logic (for the explanation) and win probability added (for evidence).
With regards to logic, I will turn to a brief column supporting the decision from Brian Burke, who is a member of ESPN's Stats & Info group and the preeminent forerunner in the football analytics movement. While citing the piece might seem like an appeal to authority, his logic is sound and I encourage you to read it. It basically boils down to this: when down 15, a team knows it needs to score two touchdowns where one is followed by a converted two point attempt to tie the game. So the team at some point is going to have to go for two, assuming it scored the requisite two touchdowns. Most teams, as I alluded to above, prefer to kick the extra point first and delay the potential of being eliminated from the contest and then wait to go for two after a potential second touchdown. Burke's argument (which is generally accepted by analytics-types) is that instead of waiting, immediately going for two gives the team immediate feedback on its chances of winning the game, forgoing the period of uncertainty about the success of going for two, and allows the coaching staff to operate in such a way that maximizes win probability for the remainder of the game without the uncertainty of the result of the two point conversion. Either way the Cowboys would have to go for two at some point if they hoped to tie the game down 15. Going for two early gave the Cowboys additional information and allowed Mike McCarthy and Kellen Moore to make decisions and play-calls that maximized their chance of winning the game. Coaches too often are scared of embarrassing themselves and losing a game earlier than many would expect (this is the sort of logic that led to Anthony Lynn punting the ball to the Chiefs in a sudden-death overtime). McCarthy tossed optics aside and made the decision that gave his team the best chance to win.
If this sort of logic does not seem sound, or you scoff at my appeal to authority, let me present you with some data to back up Burke's logic and show that going for two is the correct decision. First, let us assume that when kicking the extra point, the Cowboy would be successful. This is not actually true: since 2015 when the extra point was moved back, teams have been successful on about 94 percent of the attempts. For ease of analysis, however, we are going to assume that the Cowboys would automatically get the point if they kick the PAT. Kicking the PAT would put the Cowboys down eight points. By going for two, the Cowboys would be faced with one of two scenarios: they would be down seven points or the deficit would stay at nine points. Since 2015, teams have been successful on about 47.9 percent of their two point attempts. For rushes, the success rate is 54.9 percent and for passes a 45.6 percent success rate. For additional context, the Cowboys did run the ball on their two point attempt, but lets assume that they are an average team in this situation with average play-calling tendencies, so the probability of success is 47.9 percent. Next we consider the win probability added in each situation relative to the win probability at an eight point deficit. Since 1999, teams that are down eight points at a similar point in the game to the Cowboys have a win probability of 13.5 percent. Down nine in the same situation, win probability goes down to 12.3 percent. When down seven points, the team's win probability increases to 18.5 percent. For this information in tabular form, see the following:
Converting the two point attempt would add about five percentage points to the Cowboys win probability. Going for two and failing would cause the Cowboys to lose just 1.2 percentage points of win probability. Therefore, the magnitude of win probability added in the case of success is 4.17 times larger than the magnitude of win probability lost due to failure. Using a similar formula to the one for calculating the break-even point of attempting a stolen base, but instead of using run expectancy we use win probability added, the break even rate for going for two in the Dallas' situation is just 19.4 percent. Remember, teams convert on two point conversions at a 47.9 percent rate. That is about 2.5 times the size of the break-even rate and that is without considering the extra benefits of running the ball on such an attempt. So, without using any of Burke's logic, the win probability arithmetic shows that going for two in this scenario is actually the overwhelmingly obvious decision here. Kicking the PAT in this situation makes no sense and McCarthy should be commended for both defying conventional wisdom and calling for the smart play, despite not actually converting the two point attempt. And yet, the Cowboys still won.
Many are going to point to this unorthodox decision and criticize McCarthy because what he did flew in the face of conventional wisdom. In a sport where front offices still choose running backs in the first 10 picks, teams run the ball often on early downs, and coaches make decisions based on the optics if that decision fails, seeing McCarthy make this decision in such a pivotal game for the Cowboys was refreshing. Hopefully other teams learn from this and see how it was the correct decision even though they failed. The fact that the Cowboys eventually won the game, for better or worse, might nudge others in the right direction (making decisions based on results instead of process puts you at the mercy of small samples and/or variance in outcomes). Even if teams choose to go this direction because of the result, us viewers will be in for a better viewing experience with more efficient football.
play-by-play data via nflfastR
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