Deep Stats Offensive Review: 2017 Wasn't All Roses

By Craig Fritz on June 6, 2018 at 1:35 pm
Penn State Quarterback Trace McSorley
Adriana Lacy - Roar Lions Roar

Last week, we took a triumphant tour through the major improvements in S&P+ made by the Penn State offense in 2017. Now it's time for part two of our analysis, the areas were the Penn State offense declined significantly (more than 15 spots nationally) in any S&P+ metric compared to 2016. Fortunately, this is a much shorter list.

For those reading for the first time, S&P+ is an advanced statistical system designed by Bill Connelly of Football Study Hall and SBNation. Bill shares a bit about why he created S&P+:

"My goal throughout 10 years of working with college football advanced stats has been to dial in to what actually wins and loses games and evaluate teams appropriately. Since 2007, I have been collecting play-by-play and drive data in an attempt to create tempo- and opponent-adjusted measures that evaluate teams as honestly as possible." - Bill C.

Those are the broad strokes, and here's another helpful glossary. Let's get to it. 

overall 2016 rank 2017 rank difference
explosiveness 2 19 -17
  • As we discussed in part one, the massive upswing in efficiency (+72) more than makes up for the modest decline in Explosiveness, so this isn't too concerning. While the 2016 offense was often all-or-nothing, the 2017 version still hit huge plays with regularity while also being able to grind out first downs over and over.
passing 2016 rank 2017 rank difference
Passing Isoppp 4 51 -47
adjusted sack rate 25 56 -31
  • This capsule shows that while explosive plays still happened, they were more likely to be running plays. Recall that IsoPPP is the Equivalent Points Per Play (PPP) average on only successful plays. This allows us to look at offense in two steps: How consistently successful were you, and when you were successful, how potent were you? While Rushing IsoPPP jumped 61 spots, Passing IsoPPP fell significantly. There just weren't the chunk scoring plays in the passing game that we saw in 2016.
  • Additionally, more poor marks for the offensive line here. Too many free runners led to a sizable decline in protecting Trace McSorley.
passing down s&p+ 2016 rank 2017 rank difference
Passing down Isoppp 6 25 -19
passing down sack rate 46 104 -58
  • The drop in Passing Down IsoPPP isn't too concerning here. Penn State generally got what it needed in obvious passing situations. This tells me that most of the passing game IsoPPP decline came from a drop in explosive passing plays on standard downs (first downs, second-and-7 or fewer, third-and-4 or fewer, and fourth-and-4 or fewer).
  • [Long whistle] Man, that obvious-passing-situation sack rate is bad, and something that could be cleaned up significantly.
offensive footprint 2016 rank 2017 rank difference
standard down run rate 44 109 -58
passing down run rate 68 110 -42
  • All this means is the Lions ran less in all situations than last year. The national average for Standard Down Run Rate was 60 percent. Penn State ran it 51.9 percent on Standard Downs. The national average for Passing Down Run Rate was 35.3 percent, and the Nittay Lions rushed 26.4 percent of the time in obvious passing situations, which, yeah, that seems about right.
special teams 2016 rank 2017 rank difference
special teams s&P+ 11 88 -77
FG value (per kick) 19 124 -105
kickoff success rate 30 59 -29
  • THUD. YIKES. WOOF. Place kicking was an unspeakable tragedy for Penn State in 2017. What was a legitimate strength a year prior turned into a complete liability last year. Without major changes in personnel, it's almost unfathomable how this precipitous drop occurred. If you're looking for a single area of improvement that could be the difference between, say 9 and 11 wins, this could be it. James Franklin needs to get this corrected immediately.

This is the second post in a series looking at the year-over-year improvements or declines in performance across the Nittany Lion offense and defense. Next up we'll look at the areas of largest improvement for the defense. [Part 1 - Offensive Improvement] [Part 3 - Defensive Improvement] [Part 4 - Defensive Decline]