Most ASU fans know far too well that last year’s pass defense fell apart as the season progressed. We at ASU Devils Den decided to dig a little deeper into the the stats to see if last year was an aberration or a trend that has been brewing.
Over the course of four seasons under head coach Todd Graham, the ASU defense has given up more and more passing yards each year, while at the same time, the yards on the ground have been trending downward. Additionally, the Devils have faced more and more pass attempts each season. Makes one wonder why offensive coordinators have been dialing up more pass plays against the Devils each year?
There is a lot of factors that go into a football game, and in this analysis, we have focused on just one of those factors; how an opposing quarterback performs against the ASU defense compared to how that same quarterback performs against all the other opponents he faced in the same season. It is similar to another analysis we did back in December using the same metric in a different fashion.
Statistically speaking, the combined quarterbacks that the ASU defense faced were better overall in 2013 than they were in 2012, and then again, better overall in 2014 than 2013. Even though ASU was facing better overall quarterbacks in 2013 and 2014, the overall performance of those signal callers against the ASU defense was even better. Then in the 2015 season, the overall rating of the combined quarterbacks ASU faced dropped to the lowest level in any of those four years, at the same time, their overall quarterback rating against the Devil pass defense was the highest ASU allowed during Graham’s tenure. In effect, no matter what the level of overall performance was of the quarterbacks ASU faced, each year those quarterbacks had increased success against the Sun Devils defense.
What are the trends telling us? Was the talent on the defense slipping each season? Or was it that the more familiar opponents were with the ASU defense, the better their quarterbacks did against the Devils?
It appears that the Devils haven’t done well against opposing quarterbacks when they were ranked, as compared to when they were unranked, even though they faced a better group of quarterback overall when they were unranked. In fact, in marquee games where both teams were ranked, the ASU pass defense performed its worse in terms of opponent quarterback ratings. The overall rating for the quarterbacks in those marquee games would have placed them as a top 20 quarterback rating in the 2015 season.
Why is it that the ASU pass defense seems to have under-performed when they were ranked heading into a game? Why did the Devils defense perform poorer against opposing quarterbacks when both teams were ranked, compared to only when the opponent team was ranked?
In ASU’s first conference game of each season surveyed, the Devil defense performed at its worst. Although the Devils faced some stellar quarterbacks in those games, each one of them did better against ASU than their overall rating against the rest of the opponents they faced that season. The combined rating for the quarterbacks facing ASU in its first Pac-12 game each season would have placed them overall as the number one rated quarterback in any of the four seasons. In fact, the highest annual quarterback rating in any of the four years was 184.85.
The Devils pass defense also seemed to have difficulty in post-season games. Could the extra time to prepare for Todd Graham’s defense be the primary factor? Four of the five quarterbacks the ASU defense faced in the post season outperformed their overall season ratings. Only Keenan Reynolds who was just a freshman in the 2012 Kraft Fight Hunger Bowl, and threw only twelve passes for Navy’s run-heavy attack, had a lower rating against ASU than against the other opponents he faced during 2012 the season.
What the Numbers Say
Two things seem to emerge from the analysis in terms of conclusions. First, more practice and film breakdown time for opponents seems to be an enemy of the ASU defense. Additionally, the defense over the course of the past four years as a whole doesn’t seem to do well when there is an extra importance associated with the game. The fact that, overall, opposing quarterback seem to be doing better and better against the ASU defense as time goes along possibly suggest that the Devils may need to address a talent issue or make some changes to its current defensive structure or scheme.
As far as the under-performance in games where they are ranked nationally, could it be a case where ASU may just perform better as an underdog, or maybe the defense puts too much pressure on itself in games where they are either ranked or playing a seemingly important games against ranked opponents? Both possibilities seem to point to a coaching issue rather than a talent issue.