As the season nears, there is one question that is dominating the minds of Michigan State fans everywhere -- how well is the offense going to do with Andrew Maxwell at the helm.
Well, my buddy Danny did a little statistical analysis of how teams fare after losing a quaterback such as Kirk Cousins -- a player drafted in the first four rounds of the NFL draft. He also threw an extra piece together on how teams fare when the new quarterback was a three or four-star recruit.
The goal is to compare offensive production during and after a QBs final year using Offensive S&P (defined here: http://www.footballoutsiders.com/stats/ncaaoff).
Here is what he found: (in a switch to the first-person in which "I" means Danny)
To start, I took all QBs that were drafted between 2006 – 2011 in the first 4 rounds that A) Played FBS Football in his final year at school and B) Attempted at least 65% of his team’s passes in his final year. 29 QBs qualified in that time frame. Then, I compared the Offensive S&P of each QB during his final year in college and the year after he was drafted. Using this projection, Michigan State’s Offensive S&P would drop to 100.2 (closest comparison from last year is Hawaii).
I wanted to refine this further, so I looked at a few factors to try and improve this calculation as it applied to Michigan State. These factors were: Whether or not the head coach remained, the Rivals rating of the new QB replacing the drafted QB, how long the new QB had been in the system, and a further refinement of where the QB was drafted.
Within these factors, only the Rivals rating and the round where these QBs were drafted were found to improve the correlation.
In looking at round, I removed all first round QBs, leaving 15 second, third, and fourth round QBs. (I did not have enough third and fourth round alone QBs to come up with a credible comparison). Using this projection, Michigan State’s Offensive S&P would drop to 99.6 (Closest comparison from last year is Wake Forest).
Next, I used the teams that were replacing a QB drafted in the first four rounds that were replacing the QBs with a 3 or 4 star prospect (Andrew Maxwell was a borderline 4 star QB, and it was the only way I could have enough to make a credible comparison).Using this projection, Michigan State’s Offensive S&P would drop to 102.7 (closest comparison is Bowling Green).
Finally, I used all the QBs that qualified for both refinements. 11 QBs fit the qualifications. Using this projection, Michigan State’s Offensive S&P would drop to 101.9 (closest comparison being Vanderbilt).
The chart at the right shows the S&P for teams with a quarterback drafted rounds 2-4 and replaced by a 3/4-star recruit.
Well, with these projections in mind, what does it mean in terms of how many points we can expect MSU to score next season? Good question. I looked at teams that were within 0.5 of each projection and teams that were within 0.5 of MSU’s Offensive S&P output last season to give a sense of what we can expect. Using all the other projections, the projected PPGs drop to 27.1, 26.9, 27.5 and 28.0, respectively.
In 2011, the Kirk Cousins-led offense had an Offensive S&P was 106.8 -- which is on average about 29.3 points per game, which MSU eclipsed by averaging 31.0 points per game. The offense should go down to about 27 points per game. So, if Maxwell has the same Offensive S&P, MSU will be projected to score 2.3 less points -- not a substantial drop-off.
In conclusion, though it is certainly possible that the Michigan State offense could completely collapse (like Auburn from 2010 to 2011), or improve (similar to Northwestern from 2009 to 2010, when Dan Persa replaced Mike Kafka), I would expect that the dropoff in offensive production would be between 3 to 4 points per game. This is a significant drop, but not one that is so drastic that cannot be overcome by, for example, a defense that was top 8 last year by S&P and returns eight of 11 starters.
(Bearing in mind, many of these schools might not have lost as many wide receivers as Michigan State has -- but also might not have the same returning experience on the offensive line.)
When Drew Stanton was a senior in 2006, he took just 64% percent of the snaps, so he did not qualify for this study. The Offensive S&P 99.1, however, in the ensuing season with Brian Hoyer at the helm it went up 114.1. Keep in mind, the change from John L. Smith to Mark Dantonio could have had a SLIGHT -- ahem, massive -- impact on these numbers.
Thanks to Football Outsiders (footballoutsiders.com), Rivals (rivals.com) and College Football Reference (http://www.sports-reference.com/cfb/) for providing the data used for this study.