In college, I had a joke with a friend. Everyone in the stadium would clap with a three-yard play on 1st and 10. If the defense gives up just two more three-yard plays it is 4th and 1. The offense is looking at two plays where it can either throw or run. Football in 2020 has gotten more sophisticated. Metrics, such as Expected Points Added (EPA), can give us an estimate on how much each play contributed to the offense or defense scoring next. The simplest way to calculate EPA is by taking the average of points scored on a drive for a given down, distance, and field position both before and after the play. The difference in these values is the EPA. If the offense “wins” the play, the EPA is positive. If the defense “wins” the play, EPA is negative. For this analysis, I used the EPA value as calculated from the cfbscrapR package.
One way of judging the success of a team over time can be to look at their cumulative EPA (cEPA). Plotting this value can allow us to easily see when the offense or defense was playing at its best or worst over the course of the season. For this exercise, I threw out plays that occurred during garbage time (43-point lead in 1st, 37 in 2nd, 27 in 3rd, 22 in 4th). This allows us to judge a team when all run/pass decision making is still on the table.
So, what has the last six years of Husker offenses looked like by cEPA? Inconsistency has notably marked each season. 2014 started strong before tailing off later in the year. The 0-6 start in 2018 had bad offensive play early in the season before picking up in the second half. The peak of the Nebraska offense occurred in 2014 with a value of 70.4 cEPA. This was the 29thhighest peak of 2014. The offense bottomed in the 2017 season during the Tanner Lee era.
The 2019 season was a disappointing one – especially for the offense. Only 33 offense peaked lower than the Huskers at 9.98 cEPA. The peak occurred at the end of the Illinois game. Nebraska’s average EPA this season, -0.04, ranked 89th in the country. Across the Big Ten, only Rutgers, Maryland, Illinois, and Michigan State had worse offenses in terms of average EPA. The Nebraska offense hit its season low on a four-yard loss on a run by Wan’Dale Robinson in the third quarter of the Purdue game.
Good things could be coming in 2020 for the Nebraska offense. The two best Oregon seasons in the last six years came with Matt Lubick and Scott Frost on staff. The Oregon offense had a max cEPA of 277.4 in 2014 and 158.1 in 2015. While expecting Adrian Martinez (or Luke McCaffery) to win the Heisman next year may be a stretch, a consistent season from the obvious would be a massive improvement over the past five years.
The best offense of the last six years was Joe Burrow’s LSU squad. It peaked with a cEPA of 316. Its average EPA was also the record at 0.36. Four 2019 offense ranked in the top eight average EPA of the last six seasons – LSU, Alabama, Ohio State, and Oklahoma. The Sooners are also responsible for four of the top 9 offense over the last six years.
Finding consistent offense in 2020 will be a major key in the Huskers returning to bowl action and contending for a Big Ten West title.