Open Field & Second Level Yards

As we try to understand the rushing game and the offensive line play through a statistical lens, we must try to determine which part the offensive line plays and which part the running back plays. In our last post we looked at power success and stuff rate, which are directly related to offensive line play. In this post we will go over open field and second level yards which are both in direct relation to the ability of the rusher along with the ability of the offensive line to open rushing lines.

Second Level Yards

Second level yards are the amount of yards a rusher gains between 5 and 10 yards. It is calculated first by counting each rush that went for 6 yards. Next, do the same for all rushes that went for 7 yards and multiply it by 2, and do that for all rushes up to 10 yards. Then, count all rushes that result in 10 or more yards and multiply it by five (6 yard rushes x 1 + 7 yard rushes x 2 + 8 yard rushes x 3 + 9 yard rushes x 4 + 10 or more yard rushes x 5). This gives you total second level yards. Once you have the total second level yards, you then divide it by total rushes (not total second level rushes).

Second level yards show how well the offensive line opens rushing lanes for the rusher. High second level yards with a low stuff rate can show a very good offensive line.

Since 2014 BHP has rushed 1,006 times and gained 1,378 second level yards for a second level yard average of 1.37 yards per rush. In comparison, BHP’s opponents rushed 785 times for 602 second level yards an average of 0.77 second level yards per rush. BHP gained 78% more second level yards per rush (2ndLev/r) than their opponents since 2014.

There is a distinct difference in BHP’s total 2ndLev/r average and BHP’s 2ndLev/r average in playoff games. BHP’s 2ndLev/r average in playoff games since 2014 is 1.09 yards per rush which is a 20.1% decrease in the 2ndlev/r average.

Open Field Yards

Open field yards are rushing yards that are gains of more than 10 yards gained from the line of scrimmage. This is calculated by subtracting 10 from any rush that is over 10 yards (for example a 15 yard rush gets 5 open field yards). Once total open field yards are calculated, they are divided by total rushes to get the open field yards per rush average.

Open field yards can show us more about the ability of the rusher turning rushes into explosive plays, but determining the percentage of total yards can show how adept the offensive line is at creating opportunities to gain open field yards.

Since 2014, BHP has rushed 1,006 times for 2,653 open field yards which is a 2.64 open field yards per rush. In that same time period, BHP rushed for 6,304 yards. Knowing this, we can determine that 42.1% of BHPs rushing yards since 2014 came from open field rushes.

To put that into context, BHP’s opponents since 2014 have rushed 785 times and gained 710 open field yards, a 0.91 open field yards per rush average. In that same time period, their opponents have gained 2,254 rushing yards with 31.5% resulting from open field yards.

Just as with the second level yards, BHP drastically decreased their open field yards per rush average in the playoffs. Since 2014, BHP decreased their open field yards per rush from 2.64 yards per rush to 1.88 yards per rush in the playoffs (a 28.8% decrease). This is in conjunction to the increase of their opponents’ average in the playoffs. BHP’s opponents averaged 0.91 open field yards per rush since 2014 and in the playoffs they increased this to 1.12 open field yards per rush (a 23.1% increase). For the most part this can be explained by the increase in the quality of the opponents, but it will be interesting to see the pattern as we move from regular season to post season play this season.

Conclusion

After understanding second level and open field yards, we can now couple it with our understanding of power success and stuff rates to build a measure of offensive line play. As we go throughout the season, we can compare this year’s team and offensive line to the historical data we have to see if we can extrapolate any conclusions on how well they played compared to past teams.