Football doesn't lend itself to "sophisticated" statistical analysis quite like baseball does. The entire game of baseball essentially boils down to a series of one-on-one confrontations (between pitcher and batter, for example, or fielder vs. ball), the outcome of which is easily measurable (a batter either gets a hit or he doesn't, a hit is a single, a double, a triple, or a homer, etc.). In the NFL, there are 11 moving parts on both of sides of the ball that largely have to work in unison to make anything happen. There are no traditional statistics to measure the play of an offensive lineman, for example, or anything but the most rudimentary stats to measure the effectiveness of, say, a cornerback (interceptions and passes defensed don't tell the whole story).

There are, however, a couple of websites that have made inroads into the world of in-depth statistical analysis for the NFL. The two most prominent of these are Football Outsiders (FO) and Pro Football Focus (PFF). Others include KC Joyner's work at ESPN and ESPN's recently unveiled and shamelessly over-promoted Total QBR statistic. From time-to-time, I plan to use these sources (primarily FO and PFF) to enlighten you, trusty VikesCentric reader, on... well, anything that strikes my fancy as being more than passably interesting to Vikings fans.
An important caveat here is that there is a huge element of humanity involved in how both FO and PFF compile their advanced statistics. By that, I mean that they aren't able to simply take "traditional" stats that are easy to measure, twist them up in impressively mathtastic ways, and spit out a new stat that more accurately describes an individual player's performance (like a baseball sabermagician might do when referring to a pitcher's FIP, for example). Instead, they have an army of presumably intelligent people that analyze every play of every game in extremely minute detail. This is referred to, generally, as game charting. And it's not for the faint of heart. According to PFF, charting a single game takes roughly 16 hours. These people are intimately familiar with their televisions and the pause/rewind/slo-mo functions of their DVR remotes. And, as with any human endeavoer, it involves a certain amount of subjectivity on the part of the game charters. A play deemed successful by one charter may not necessarily be graded the same way by another, etc. In any case, after the charting is complete, FO and PFF have their own systems of grading the performance of, say, a cornerback or an offensive lineman.
Which brings me to a nice starting point; the Vikings offensive line, which by most accounts was expected to be a serious cause for concern coming into the season. While the results have been mixed – particularly in terms of pass protection – the game charters and math wizards would have us believe there are several notable trends emerging along the Purple's offensive line:
1) Phil Loadholt is quietly becoming a very good right tackle.
2) John Sullivan isn't as bad as you may have been lead to believe.
Let's begin with Loadholt. According to PFF, Loadholt registered the highest single-game run-blocking score of his career during last week's win over the Cardinals. Loadholt, matched up primarily with Pro Bowler Darnell Dockett, paved the way for the Vikings to average 7.0 yards per carry on runs to either side of Loadholt a week ago, and according to the ICSIWMOTE Index that I just made up (I Can See It With My Own Two Eyes Index), he threw key blocks on two of Peterson's three touchdown runs. Loadholt was given a +3.8 rating for run blocking last week, bringing his yearly total to +9.4. Generally, a grade of 0 means a blocker did essentially what you'd expect the average NFL offensive lineman to do on any given play. A grade of +0.5 or +1 (up to a max of +2) is an indication that the player made "a positive intervention on the game" of varying degree, a negative grade means the opposite (a "negative intervention," I suppose... soon to undoubtedly be coined a "T-Jack"). In the Loadholt example, you add up all the zeroes, positives, and negatives for every single play of last week's game to eventually arrive at a total of +3.8. It's science.
Putting it in a little more perspective, Loadholt's cumulative +9.4 run blocking grade ranks first in the NFL through five weeks, well ahead of the Packers' Bryan Bulaga and the Patriots' Matt Light. If that hasn't yet sunk in, according to smart people who watch every play of every game over and over and over (and over) again for up to 16 hours at a time, Phil Loadholt is the best run-blocking tackle in all of football. Even if you include guards and centers, Loadholt is still the No. 2 run-blocker in the NFL, according to PFF. Side note: For the purposes of this analysis, I'll conveniently overlook the fact that Loadholt has graded out at -9.7 in terms of pass blocking, due primarily to the fact that he allowed six quarterback pressures, a hit, and a sack in the come-from-ahead loss to the Lions three weeks ago. We're talking about run blocking here, folks, not pass blocking.
The Football Outsiders tend to agree with this assessment. According to FO's "adjusted line yards" stat (for a detailed description and to see the full rankings, click here, and consider yourself warned that it includes terms like "regression analysis," "normalize," and "move out of your mom's basement already."), the Vikings' offensive line ranks third in the NFL on runs over right tackle, and eight in overall run blocking.
As for Sullivan, he's also been noticeably better this year than he was during an injury-plagued 2010 campaign. Sullivan has graded out positively in the running game in all but one game thus far, and at a cumulative +4.4 for the season, he ranks as the No. 5 run-blocking center in the NFL. Last year, Sullivan earned a cumulative -7.9 grade, and only garnered positive rankings in five of the 14 games in which he played significant snaps. For the record, Loadholt came in at a whopping -14.3 in run blocking last season.
The idea of Sullivan and Loadholt creating running room can also be shown through an analysis of Adrian Peterson's yardage gained by "rush direction." PFF's analysis shows that Peterson has gained 8.4 yards per carry on rushes between Sullivan and right guard Anthony Herrera, 4.7 per carry to the right of Herrera (and left of Loadholt), and 4.3 per carry over right tackle. As previously noted, FO ranks the Vikings as the third-best team in terms of runs over right tackle. And finally, if you're looking for any additional corroboration from a more "traditional" source, Peterson's situational stat page on Yahoo indicates that he averages 5.9 yards per carry when running "right" and 5.7 when running "wide right".

Another side note Jared Allen and Brian Robison migh find interestig heading into Week 6: The Bears' starting tackles from 2010 (and for most of 2011 after first-rounder Gabe Carimi got injured), D'Marcus Webb and Frank Omiyale ranked as the 77th- and 75th-worst tackles in the NFL last year (out of 78 that qualified for the ranking), according to PFF. In other words, with only one exception (Cardinals' revolving door Levi Brown, who finished 78th overall), neither of the two starting tackles for the Bears would have been good enough to start on any other team in the NFL.
Christian Peterson is the Operations Manager at LeagueSafe.com and is a contributor to Vikings.com, the 2011 Maple Street Press Vikings Annual, and the Fantasy Football Weekly radio show on Saturday Mornings on KFAN 100.3 FM.