Run Defense Dominates in the Playoffs

In the last post I indirectly analyzed playoff games by looking at regular season games that only featured opponents who both went on to win at least 10 games. We saw that teams with the better running games actually won less than 50% of the time.

In this post, I'll look at actual playoff games directly. Compared with the 114 "good vs. good" regular season games I looked at yesterday, there were 50 playoff games, plus 5 Super Bowls, in the 2002 through 2006 seasons.

The table below lists the winning percentage of the team with the superior season-long performance in each stat. In other words, the team with the better [stat] won [x] percent of the time. The regular season good vs. good match-ups are also listed for comparison. (The home win percentage excludes the five Super Bowls during the period.)

Stat	Good vs Good	Playoffs
Home	59.6	64.0
O Run	45.6	45.5
D Run**	48.2	67.3
O Pass*	52.6	63.6
D Pass	51.8	56.3
O Int Rate	50.9	58.1
D Int Rate	55.3	58.1
O Fum Rate**	55.3	40.0
D FFum Rate	54.4	54.5
Pen Rate	47.3	52.7

** = good vs. good / playoff difference is significant at the p=0.05 level
* = good vs. good / playoff difference is significant at the p=0.10 level

The home team won more often in the playoffs than in good vs good regular season match-ups, which is expected because higher seeded teams host the playoff games.

The team with the better run efficiency won only 45.5% of the 55 playoff games during the '02-'06 period. Keep in mind the small sample size could make these results misleading. 45.5% is only 2.5 games below 50%. But the result echoes the same result for the regular season good vs. good match-ups.

Defensive run efficiency is a different story. Although the team with superior run stopping ability won only 48.7% of the regular season good vs. good match-ups, it won 67.3% of playoff games. This is a striking difference to say the least, especially considering how unimportant run defense is based on regression models of regular season games.

The passing game stands out as well. Both offensive and defensive passing stats appear to be more important in the playoffs. Interception rates also appear very important.

Another striking result is that of offensive fumble rates. The team with the lower fumble rate wins only 40% of playoff games. As one of the more random stats, it's not too surprising to see a spurious result for fumble rate, but 40% is fairly low, even for such a small sample size.

I suspect that coaches may become too conservative in the playoffs, relying on the run. This might explain why having a good running game doesn't help teams win and why the ability to stop the run suddenly becomes very important in the playoffs.

My own gut feeling is that coaches don't coach to win. They coach to avoid a loss. It sounds inane, but there is a difference. Maybe the play-calling in the playoffs becomes even more timid. But then again, perhaps the January weather has something to do with it. Previous research has established the importance of climate, especially when dome teams play outdoors. Weather may explain the 67% win percentage of teams with the better run defense. Defense may win championships after all, particularly run defense.