In week 6, the Cowboys traveled to MetLife Stadium to face the Jets in what looked to be an easy win for Dallas. It was not: Sam Darnold injected some much needed offense into a lifeless Jets team, highlighted by a 92-yard touchdown pass to Robby Anderson. New York played well, but Dallas did have a chance to steal a come-from-behind victory. To do that, however, it would have required Jason Garrett to maximize his team’s win probability with thoughtful end-game strategy. Instead, Garrett made two key blunders in the 4th quarter of Sunday’s game, lowering the Cowboys chances of completing a comeback.

Seven years ago, I wrote that when trailing by 15 points midway through the fourth quarter, a team that scores a touchdown should go for two. Midway through the fourth quarter, Dallas trailed the Jets by 12 points — which, math experts may quickly realize, is a 15-point lead minus one field goal. Therefore, the same logic applies, and you’ll see why in a moment.

Ezekiel Elliott rushed for a touchdown with 6:36 remaining, and this is when the Cowboys should have gone for two. And this is not Monday morning quarterbacking: I tweeted as such in real time. Instead, Dallas sent out the kicker and cut the lead to 5 points. The Jets responded with a field goal, which highlighted the problem.

That made it a 8-point game, which is why it was a mistake to not go for two earlier. Just like when you score a touchdown down by 15, you want to go for two to make it either a 7-point game or a 9-point game. When trailing by 15, you need to score two touchdowns and convert a two-point conversion. If you convert the two-point conversion, it doesn’t matter whether you go for two after the first touchdown or the second touchdown (although, of course, only if you go for it the first time can you try to win the game with a 2-point attempt after the second touchdown). If you miss the two point conversion attempt, however, it makes a very big difference.

Dallas was ignorant of the situation: by going for 1, the Cowboys did not know that they would go on to fail on their two-point conversion attempt. Here’s what actually happened: after the Jets kicked a field goal, Dallas took over with 3:23 remaining, and casually drove down the field, scoring with 47 seconds left. The Cowboys then missed the 2-point conversion play, effectively ending the game (more on this in a minute).

Now, let’s pretend that Dallas went for 2 after the first touchdown. And, since we have no reason to believe the result would be any different, let’s assume the Cowboys failed on the try. In this world, Dallas would be trailing by 9 with 3:23 remaining, the Cowboys would be in hurry up mode. In the real game, Dallas ran only four plays before the two minute warning, but that wouldn’t have been the case if the team had been down by 9 points. And here was the worst part: Dallas got to the Jets 16-yard line with 1:24 remaining, and then purposely bled the clock so that the Jets wouldn’t have much time left to counter with a score! The Cowboys let 26 seconds run off the clock near the end of the game because they were trying to drain clock… because they didn’t know they were going to miss the 2-point conversion! This is why you always go for 2 first when trailing by 15 (or 12, in this case) in the middle of the fourth quarter. There is no upside to kicking the extra point first, and this was a big blunder that cost Garrett’s Cowboys a chance to win the game.

Had Dallas gone for 2 and missed early instead of late, what would have happened? The Cowboys could have scored a touchdown with about 1:30 remaining instead of 43 seconds left, and kicked it deep to the Jets. They would have had all three timeouts remaining, and could hope for a 3-and-out; that would put Dallas in a situation where they’d have the ball at around their own 20 yard line, with 1 minute to go, down by 2 points with no timeouts. And given that they had already kicked a 62-yard field goal in the game, that would have been a pretty decent situation to be in! Instead, by delaying the decision to go for 2, when the Cowboys missed the attempt, the game was basically over.

It is often argued incorrectly that by going for 2 first and missing, it is demoralizing and nearly kills your team’s chances of winning because you are now down by 9 late in the game. I can assure you that it is more demoralizing and worse to your team’s chances of winning to have to kick off, while losing, with 40 seconds left in the game.

I wrote earlier that Garrett made two key blunders. What was the second? The Cowboys had all three timeouts for most of the second half. I noted earlier that when Dallas got to the Jets 16-yard line, they began to (wisely) bleed clock. With 54 seconds remaining, facing a 3rd-and-2 from the Jets 8-yard line, the Cowboys picked up 4 yards and the first down. This brought them to the Jets 4-yard line with 47 seconds remaining. At the time, I assumed Adam Gase would do the smart thing and call a timeout. If the Cowboys were to score, with the way Darnold had been playing, the Jets would have had a real chance to kick a field goal and win the game. So when the officials stopped the clock, I was relieved to see that Gase finally made a wise decision.

He had not. It was Garrett — Garrett (!) — who had called the timeout. I was flabbergasted at the time and am even more so today. The Cowboys had all three timeouts remaining. If Dallas would go on to miss the 2-point attempt — are you seeing know how poor of a strategic decision it was that Garrett didn’t go for 2 earlier?? — then Dallas would need all three timeouts to stop the Jets. And if Dallas would go on to *make* the 2-point attempt, why would you want to give Darnold and the Jets more time?

It was an awful decision that eliminated Dallas’s chances of winning the game if they failed on the 2-point try. Onside kick attempts are basically impossible to recover now (although the Jets almost bungled this one), but had the Cowboys not called timeout, they would have still had a chance even if they missed the attempt. Dallas could have kicked deep and stopped the Jets three times using all three timeouts (a pretty likely scenario as the Jets surely would have played it safe). The Cowboys wouldn’t have had a great chance, but would have had a few plays to get in position to try a long field goal to win the game (and, as I noted earlier, I would have expected Gase to call timeout if Garett had not; either way, the Cowboys shouldn’t have called timeout). In any event, a small chance is much better than no chance.

These two decisions were bad, and the effects were compounded upon each other. Garrett is a very good coach when it comes to developing players, hiring assistants, and putting together an offensive scheme. But end-game strategy, deciding when to kick, punt or go for it, and figuring out how to use your timeouts is not a skill you learn from being an NFL quarterback or coach. And it is not a skill that, 10 years into his head coaching career, Garrett seems to have acquired.