Yesterday we looked at the Hokies' improved offensive efficiency in 2009. Today, we take a look at the defense. Unlike those offensive number, a lower number is better for the defense. And despite late struggles against the run the defensive numbers also improved for Virginia Tech.
After the jump are the full details.
Most of the raw data for these tables comes from cfbstats.com. If you don't have them bookmarked you don't know what you're missing out on.
If you remember last year's numbers you know the Hokies held their own against the run but struggled against the pass. This year the defense improved its efficiency across the board despite replacing players at key positions, including boundary corner, mike linebacker and defensive tackle.
A quick recap on these efficiency numbers: They measure how the Hokies performed against expectations against each opponent and overall using stats from conference games only. For the defense you take the opponents' average yards per play (or carry or pass attempt) and multiply it by the number of plays they ran against Tech to give you their expected yards. Then you compare that number to their actual production. For the rushing numbers, you have to take out the sacks.
And awaaaaaaay we go.
Abbreviations: YPC - yards per carry (rounded); Rush - opponent carries minus sacks; ExYds - expected yards for the opponent (rounded); Yards - opponent yards with sacks taken out; Eff - VT efficiency.
| Opponent | YPC | Rush | ExYds | Yards | Eff |
| Miami | 4.7 | 31 | 144.7 | 87 | 0.601 |
| Duke | 2.5 | 28 | 70.9 | 55 | 0.776 |
| Boston College | 4.2 | 26 | 109.7 | 75 | 0.684 |
| Georgia Tech | 5.5 | 62 | 344.0 | 320 | 0.930 |
| North Carolina | 4.1 | 40 | 165.7 | 191 | 1.153 |
| Maryland | 3.9 | 25 | 97.2 | 160 | 1.646 |
| NC State | 4.3 | 20 | 85.2 | 74 | 0.869 |
| Virginia | 4.0 | 35 | 139.1 | 194 | 1.395 |
| Season | 4.4 | 267 | 1165.5 | 1156 | 0.992 |
The Hokies improved slightly against the run in 2009, but image what these number might have been had they not struggled stopping the run in the last four conference games. The number against North Carolina especially sticks out for obvious reasons.
On to the passing numbers where Tech was fairly dominant in 2009.
Abbreviations: YPA - opponent's yards per attempt (rounded); Pass - opponents pass attempts; ExYds - expected yards for the opponent (rounded); Yards - opponent yards; Eff - VT efficiency.
| Opponent | YPA | Pass | ExYds | Yards | Eff |
| Miami | 8.2 | 25 | 204.4 | 150 | 0.734 |
| Duke | 7.7 | 40 | 309.4 | 359 | 1.160 |
| Boston College | 6.1 | 28 | 170.5 | 118 | 0.692 |
| Georgia Tech | 9.4 | 7 | 65.8 | 51 | 0.775 |
| North Carolina | 5.8 | 29 | 167.5 | 131 | 0.782 |
| Maryland | 6.1 | 33 | 167.5 | 104 | 0.518 |
| NC State | 7.6 | 29 | 220.6 | 245 | 1.111 |
| Virginia | 5.0 | 22 | 110.2 | 120 | 1.089 |
| Season | 6.9 | 213 | 1473.9 | 1278 | 0.867 |
That's a huge improvement even after losing Macho Harris to the NFL. What helped was the Hokies were second in the ACC in sacks in conference play, meaning opposing quarterbacks were under a lot of duress when they played Virginia Tech. While the Hokies didn't have a lot of interceptions in conference play (only six), opposing ACC quarterbacks were held to a conference-low 47.4 completion percentage and a conference-low 6.0 ypa. That will always help your efficiency.
Finally, the total yards and points.
Abbreviations: YPP - opponent yards per play (rounded); Plays - opponent plays; ExYds - expected yards for the opponents (rounded); Yards - opponent yards; Eff - VT efficiency. PPP - opponent points per play adjusted for non-offensive points (rounded); Plays - opponent plays; ExPts - expected points for the opponent (rounded); Points - opponent points minus non-offensive points; Eff - VT efficiency.
| Opponent | YPP | Plays | ExYds | Yards | Eff |
| Miami | 6.0 | 59 | 356.1 | 209 | 0.587 |
| Duke | 5.3 | 71 | 377.6 | 397 | 1.051 |
| Boston College | 4.6 | 57 | 262.9 | 163 | 0.620 |
| Georgia Tech | 6.1 | 70 | 424.2 | 360 | 0.849 |
| North Carolina | 4.7 | 71 | 330.2 | 312 | 0.945 |
| Maryland | 4.5 | 64 | 288.9 | 236 | 0.817 |
| NC State | 5.6 | 55 | 307.4 | 259 | 0.843 |
| Virginia | 3.9 | 59 | 227.2 | 295 | 1.298 |
| Season | 5.1 | 506 | 2596.3 | 2231 | 0.859 |
| Opponent | PPP | Plays | ExPts | Points | Eff |
| Miami | 0.411 | 59 | 24.3 | 7 | 0.288 |
| Duke | 0.312 | 71 | 22.1 | 26 | 1.175 |
| Boston College | 0.342 | 57 | 19.5 | 14 | 0.718 |
| Georgia Tech | 0.462 | 70 | 32.4 | 28 | 0.866 |
| North Carolina | 0.273 | 71 | 19.4 | 20 | 1.034 |
| Maryland | 0.266 | 64 | 17.0 | 3 | 0.176 |
| NC State | 0.371 | 55 | 20.4 | 10 | 0.490 |
| Virginia | 0.211 | 59 | 12.4 | 13 | 1.046 |
| Season | 0.336 | 506 | 170.1 | 127 | 0.711 |
Those numbers against Miami make me smile.
Obviously you can't judge the defense by these numbers alone, but they did a very good job holding opponents under their expected yards and points in 2009, much better than they did in 2008. Can it continue next season? I think it can provided Jason Worilds returns. A lot of Tech's defensive success is predicated on getting pressure on the quarterback and without Worilds I'm not sure how good the Hokies will be at that. That's something I'll go into in more detail later when previewing 2010.
What are your thoughts on these numbers?