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The basic numbers for the Tide's defense are astounding: No. 1 in run defense, scoring defense and total defense, to just pick three categories. And upon closer inspection, as hard as it is to believe, we may be under-estimating the unit's dominance. That starts with the talent of the Alabama lineup. According to Pro Football Focus, six of the team's 11 primary starters this season graded in the High Quality or Elite range (85 or higher). Seven of them were ranked in the top 25 nationally at their positions. Here are the grades and rankings (Shaun Dion Hamilton, who will miss Saturday's game because of an injury, is included here because he played an important role in the unit's success):

Alabama faced 10 Power 5 programs this season. Five of those featured 1,000-yard rushers -- and that doesn't account for Leonard Fournette, who missed time with injuries. No Power 5 back mustered more than 56 yards rushing against the Tide's bruising defensive line. Here are the game-by-game performances of opposing RBs (not including bowl games), with the game vs. Alabama in red.

Power 5 running backs vs. Alabama

Game

Among Power 5 opponents, the average opponent QBR against the Tide was a paltry 20. The reason: unrelenting pressure. Just ask Austin Allen of Arkansas, who was sacked on 13 percent of snaps by Alabama and was under duress or hit on another 52 percent of snaps -- both more than twice NCAA averages. Best of luck to Washington's Jake Browning in staying out of harm's way Saturday. He'll need it.

Power 5 quarterbacks vs. Alabama (% pressured snaps)

NCAA averages: 5.6% sacked, 17.7% duress/hit, 76.7% none

Jonathan Allen took home pretty much all the hardware a defensive lineman can get (SEC Defensive Player of the Year, Bednarik and Nagurski awards as best defensive player, unanimous All-American). On this play, watch Allen (93) easily discard All-Pac-12 tackle Chad Wheeler of USC (72) to make the stop:

Allen excels as a run-stopper (stops on 12.4 percent of run defense snaps, fourth nationally among 275 defensive linemen) and as a pass-rusher (created pressures on 9.7 percent of total snaps, third in the nation). Below is a breakdown of how and where he lined up -- expect plenty of Allen on the right side and inside the tackle.

Allen's 633 defensive snaps

Regardless of where he plays, Allen gets to the quarterback. His 60 quarterback pressures were first among interior linemen. Here's how he compiled them, separated into sacks, hits and hurries. Nearly half of all pressures (26) came on outside moves.

Allen's 60 QB pressures

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Led by Marlon Humphrey and Minkah Fitzpatrick (both 6-foot-1 and athletic), the Crimson Tide pass defense has very few weak spots. It allowed a total QBR of 19.0. Only Michigan (17.7) was better. Below are defensive QBR totals by zone, and areas below NCAA averages are in red. Planning on throwing a short or intermediate pass to the right or anywhere to the left? Good luck with that.

QBR allowed by section

In the month of November, the Tide defense stood resolute against LSU, Mississippi State, UT-Chattanooga and Auburn. In four games, it didn't allow a single touchdown. Below is a drive-by-drive breakdown of that impressive performance, highlighting the six field goals that accounted for all the scoring by Alabama's foes in 16 quarters of play.

Defensive drives in November

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LSU (won 10-0)

Distance to goal line →

Miss. State (51-3)

UT-Chattanooga (31-3)

Auburn (30-12)

We compared all FBS defenses since Saban started at Alabama in 2007 using two telling metrics. By Defensive Fremeau Efficiency Index (DFEI), which measures opponent-adjusted drive efficiency, this year's squad stands alone at the top. By lowest percentage of possible yards allowed, the 2011 Tide defense was better than this year's, but a pair of great showings in the playoff could put this group at the top in both measurements. Here are both metrics in one chart of FBS defenses over the past decade, with all Alabama defenses highlighted in red.

FBS team defenses since 2007

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Data from Pro Football Focus, FootballOutsiders.com and Sports-Reference.com.