Denver’s 24 point rally to win going away 35-24 on Monday Night was the latest large comeback in what is becoming a more common feature in the NFL. Over the last two calendar years, we have seen 13 different games where a team trailed by more than two touchdowns at halftime, but came back to win.

How notable is that number? Well, in the 1960′s, it happened 11 times. In the 1970′s, it was only three for the entire decade. From 1980 to 2009, the average was just under two such games per year.

I thought I would go back through the thirteen lucky (or unlucky) teams to make history in the last two years, and see what we could see about the anatomy of these games. After Monday night’s big win, Peyton Manning said that you needed all three phases to complete such a big comeback. How true is that?

Well, we should start, of course, by saying no game is exactly the same. We can look for some generalities but there are exceptions to every one. Here are some of the things that stood out to me.

1. The teams that came from behind were pretty bad offensively in the first half, and it generally wasn’t due to turnovers.

Over the last three seasons, teams have averaged about 1.7 turnovers per game. Cutting that in half would make it about 0.85 turnovers for all teams in all situations. The teams that would eventually complete a comeback from a large margin averaged exactly 1.0 turnovers in the first half, not a notable result.

Still, they only scored 3.2 points in the first half, and only two of the 13 actually scored a touchdown before the break. The culprit was simply bad offense. An average of seven first downs, and 131 total yards. The third down conversion rate was cumulatively only 29%.

In this way, Denver’s first half–fueled by two special teams turnovers that led to 10 points, plus the pick six–was atypical. If you are deceived by recency and momentum, you may have thought most of these teams were in trouble because the offense was struggling.

2. The Offense was more variable than the Defense in terms of Yards and First Downs.

What I mean by this is that there was a bigger swing in the offensive performance of the Comeback Team than the defensive performance. The first down ratio went from 7:13 to 16:9. The total yards jumped from 131 to 273 in the second half. The yards allowed improved from 226 to 142. If you are keeping score there, the offensive jump in net yards for the two halves was almost double the defensive improvement.

3. Turnovers By the Leading Team were a huge factor in the second half.

The teams entering the second half with the lead had 1.8 turnovers on average, while only three of the 13 teams attempting the comeback had one in the second half. Some of these, notably in Monday Night’s game and the Detroit rally against Dallas last year, directly led to defensive touchdowns. Others set the team up with good field position to aid the rally.

4. Special Teams was not a big factor.

Well, assuming they start holding on to the ball, I assume that is what Manning meant by contributing. The rallies, though, were not generally keyed by big special teams plays, interestingly enough. The only return touchdown in one of these rallies was DeSean Jackson against the Giants in 2010, and that came after the Eagles had come all the way back.

5. Factors like third down rates of course swung from half to half.

Third down conversion rates go a long way in explaining past outcomes, but are notoriously volatile and not necessarily predictive of the future if they are out of line with the rest of the team’s performance.

In the first half, the team that would eventually come back only converted 29% of third downs, compared to 49% for the opponent. That completely reversed in the second half, as the come back team converted 55%, compared to only 25% for the team trying to hold the lead.

6. The team trailing did not get out of balance with run/pass ratios

The team who was trailing ran the ball 35% of the time in the first half, and 39.6% in the second half. Some of this is tied to third down rates (shorter conversions are more likely to be runs), and some of it is tied to them actually getting the lead before the end of the game and running out the clock.

Meanwhile, the team holding the lead went from 47% runs to 38.2% runs in the second half as the lead slipped away.

CONCLUSION

The comebacks are on the rise because of the prolific nature of passing offenses in the NFL. Teams are better able to come from behind. Not only that, though, but the opponents know this, and realize that they have to continue to control possession and gain yards. If the running game struggles, this means passing, which means more risk for turnovers. These comebacks have been fueled in part by turnovers from the leading team, who still feels pressure to pass.

It would be incorrect, though, to assume these teams should have just run the ball (unsuccessfully). This would be the same logical fallacy that would say teams should just kneel because that leads to winning. First downs lead to winning and holding off comebacks. The passing game, and the variability that comes with it, leads to bigger swings, and we’ve seen that play out in these thirteen games.

[photo via US Presswire]