Instead of taking a close look at last week's game against the Commodores, we'll instead devote this week's statistical analysis piece to the effectiveness of Alabama's various special teams units over the course of the first six games of the season. Following next week's game we'll take a look at the defense through seven games, and then the following week we'll examine the offense through eight games.
This statistical look at the special teams units flows nicely following Nico's poll this morning about which of the special teams units most concerns Tide fans as we sit at the midway point of the regular season. Conventional wisdom has been that the various special teams units, particularly the kickoff and punt units, have hurt Bama thus far. One problem with the conventional wisdom: the statistics don't back that up.
Kickoff Unit | +2.56 in Field Position Value
Those who have read my statistical analysis piece each week this season are familiar with the concept of field position value. The average starting field position in college football following a kickoff is the return team's own 28 yard line. The expected value of an offensive possession starting at that spot is roughly 1.78 points. Any kick return that advances the ball beyond the 28 thus increases the offense's expected scoring chances (relative to the average) and thus adds positive field position value to the team, which is measured by the increased or decreased expected scoring value based on the field position at which the offense starts its possession following the kickoff.
As you can see from the heading above, Bama's kickoff unit has actually produced positive field position value for the team overall through the first six games (+2.56 points). In layman's terms, that means that if Bama's defense was facing an equally strong offense each week, the kickoff unit would have reduced opposing offenses' expected scoring output by nearly a field goal over the six games. Granted, that's not excellent, but the point here is that the impact has been positive.
In those six games, the Tide has kicked off to the opponent 43 times. On those 43 kickoffs, the opponent has had an average starting field position of its own 26, which of course means the kickoff unit has been above average in that regard. Most importantly, however, the kick return unit hasn't given up any returns that have gone beyond the opponent's own 42. That return, which happened in the Arkansas game, gave up -0.48 points in field position value. Considering the Tide has now gone through half the season, being able to say that our kickoff unit's worst moment was giving the opponent less than half a point in extra expected scoring value is something just about any coach in America could live with.
Punting Unit | + 2.04 in Field Position Value
The positive value above is going to shock a lot of people, but if you think about it, it really shouldn't. Yes, Cody Mandell's punts have been short. Yes, sometimes they have been too short. But guess what? The Tide hasn't given up a single big punt return all year. Not one. Even if your kicks are a little short, as long as you aren't giving up any significant returns (whether because of good hang time or the effectiveness of the coverage unit) you are going to beat statistical expectations, and that, believe it or not, is exactly what Bama's punt unit has done thus far this year. Like the kickoff unit, they aren't producing tons of value by any means, but more importantly they aren't giving it up either.
Through six games, the Tide has punted 24 times. Of those 24 punts, 16 (64%) have resulted in net punting yards above the college football average of roughly 33-34 yards. Remember, net punting is all that matters. A 48-yard punt that allows a returner space to return 10+ yards is less effective for the team than a 38-yard punt that results in a fair catch or a return for no gain. The punting unit's worst play came when Mandell shanked a punt in the Arkansas game, resulting in a 21-yard punt. It was ugly, and it did hurt the team in field position value (-0.46), but again, just like the kickoff unit, when your punt unit's worst moment of the first half of the year resulted in less than half a point in lost field position value, you can't complain too much.
Field Goal Success | + 0.32 in Scoring Value
This is probably not going to shock a lot of people: the Tide's field goal unit has been very effective on PAT's and short field goals, ensuring that the unit hasn't hurt the team from a value-lost standpoint, but the ineffectiveness on long kicks has prevented the unit from really producing a lot of added scoring value. The overall value of +0.32 points means that the unit has been just ever so slightly above the expected effectiveness of a college field goal unit.
Here's how the analysis works for field goals. Each field goal attempt is given an expected value based on the average success rate of a college field goal unit from that distance. For example, college kickers successfully convert PAT attempts just over 94% of the time. Thus, a PAT attempt has an expected value of 0.94, and so a successful attempt produces +0.06 points in added value while a missed attempt results in -0.94 points in lost value. Similarly, college kickers convert 35-yard field goal attempts roughly 74% of the time, meaning the expected value of an attempt from that range is 2.22 points (74% x 3 points).
Given this metric, the field goal unit has just barely broken even. Jeremy Shelley and the field goal unit have attempted 29 PAT's through six games, successfully converting 28 of them. This has actually resulted in +0.74 points in added value, since that success rate is above the national average for college PAT's. Similarly, Shelley and the field goal unit have successfully converted all six field goal attempts of less than 35 yards, which combined resulted in +2.22 points in added value. For attempts between 35-40 yards, Shelley is 2-for-3, putting the field goal unit at -0.57 points in lost value due to the missed attempt from that range. The Tide has only attempted two kicks from beyond 40 yards, both unsuccessful, resulting in -2.07 points in lost value.
In sum, the unit isn't hurting the team, doing a solid job of converting when the offense sets the unit up for PAT's and short field goals. However, the unit isn't really adding any scoring value either when the offense sets them up for long and even intermediate-range attempts. One side note, however, is that the field goal unit did add +6.83 points in value with a successful fake field goal against Arkansas.
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After looking at these numbers, my thoughts are as follows. Those who thought Bama's special teams units were hurting the team were probably being too harsh. Sure, sometimes the kickoffs and punts are short, but thus far the height of the kicks and/or the general effectiveness of the coverage teams has been enough to offset the lack of kick distance, and has effectively prevented anything approaching a game-changing return by our opponents through half the season. Meanwhile, the field goal unit has been efficient from short range, thus ensuring deep drives into opposing territory do not go for naught.
That said, it is fair to say that none of the three kicking/coverage units discussed in this piece can be considered elite. The Tide isn't consistently flipping field position with punts, isn't producing scoring value on long field goal attempts and isn't consistently pinning teams at or inside the 20 on kickoffs--but very few college special teams units are doing those things. So while there is some room to criticize here, let's not lose sight of the big picture. As everyone reading this already knows, and as our statistical piece next week will confirm, Bama's defense is truly elite. Alabama can continue to win without the special teams producing tons of value on its own. The most important thing, with such a strong defense, is for the special teams units to continue to consistently keep positive field position value (namely continuing to prevent big returns) and continue to not leave any points on the field by successfully converting on short field goals.