The tone for Adrian Peterson's day was set on the first play.
That may seem obvious given it was a 51-yard run, but it was key for reasons other than the purely obvious.
As Mark Craig of the Star-Tribune said in his breakdown of that play, the Vikings called a very straightforward play called "34 Doctor." It's an obvious run formation and the Bears knew it—or something like it—was coming.
Peterson often sees eight men in the box when it's obvious he's going to run but in this case, Chicago stacked nine with six right on the line of scrimmage.
The Vikings' scheme added three tight ends to hold the edge of the line to give Peterson extra time. Before we get to the snap, let's examine what this play already says.
This is the Vikings saying "we're coming right at you, Chicago. Try and stop us." This is the Vikings lining up to kick the Bears in the teeth.
It's exactly the sort of thing which gave them the win against San Francisco. Aggressive, straightforward football. They wanted to impose their will on the Bears early and attack the suddenly soft spot in the middle of the unit with Brian Urlacher out.
Five of the six plays opening the game were runs by Peterson. In fact, Peterson ran the ball a ridiculous 31 times while Ponder threw the ball a paltry 17.
Lest you think that Peterson's 154 yards was merely due to so many carries, Peterson averaged a fantastic five yards a carry as well.
Peterson put this team on his back early and carried them to a win. Yes, the defense played well but the game was all Peterson. When those of us who back Peterson for MVP talk about the difference he makes to this team in terms of wins and losses, this is one of the games to which we'll point.
Back to "34 Doctor," the Vikings did a great job at the snap of blocking out the Bears and keeping them from hitting Peterson in the end zone.
The whole line blocked to its left, opening a hole right where Geno Hayes (No. 58) and Nick Roach (No. 53) were standing. Of course, Roach was filling in for Urlacher and Hayes shifted over to fill Roach's spot at the strong side linebacker spot.
Attacking those two was also a theme for the day.
H-Back Rhett Ellison did a great job of eliminating Roach, while tight end John Carlson held off Hayes. If there was a miscue here, it's that tight end Kyle Rudolph missed his block of Bears defensive end Corey Wootton and nobody was left to block cornerback Kelvin Hayden.
Luckily for the Vikings, Wootton and Hayden both missed their shots as Peterson was just too quick to the hole.
Peterson juked and stiff-armed Bears free safety Chris Conte and was off to the races.
Let's not fail to point out a nice job blocking by rookie wide receiver Jarius Wright, who crossed the field to get in the way of some trailing Bears, allowing Peterson to gain another 10 to 15 yards.
While this is just one play, and a play where Peterson didn't score, it is potentially the biggest offensive play the Vikings had.
It set the tone for the game on both sides of the ball. While the Vikings' tackling left a lot to be desired, they were aggressive in pursuing Jay Cutler and attacking his wide receivers.
Peterson himself was only getting started though.
The rest of that first series was like watching a boxer throw a combination. The Vikings ran Peterson at both sides of the Bears' defensive front—left, then right, then left.
This kept the Bears from being able to set up off one tackle or the other. In this series alone the Bears allowed Peterson another 16-yard run, setting himself up for an easy-looking touchdown.
You can start out like that, but it takes commitment to the run and good blocking to keep it up.
As we pointed out earlier, the Vikings certainly committed to the run—this next play shows how his teammates blocked the heck out of the Bears for him.
It's just the second series and the Vikings have intercepted a Jay Cutler pass, returning it to the 5-yard line.
Of course, first down was a run by Peterson, straight off the left tackle, beautifully blocked by the offensive line. Major Wright prevented a touchdown with a shoestring tackle but only for a couple of plays.
On the very next play, the offense lined up with seven men on the line, with wide receiver Stephen Burton out wide to the left and fullback Jerome Felton as lead blocker for Peterson.
It was a straightforward run play. Everyone in the stadium knew it was coming.
At the snap, the line cut right and Felton hopped into the running lane, completely obliterating Roach.
Felton is a tremendous blocker who doesn't get enough attention, though I would imagine Peterson would sing his praises if you asked. A lot of teams use tight ends as run blockers, or even extra linemen, rather than fullbacks.
Certainly the Vikings do those things on occasion (for an example, look again at the first set of plays) but they do use Felton on some of the short yardage stuff, at which he excels.
Peterson hopped through the trash and was ultimately taken down short of the goal line, but it was a solid run and the Vikings just kept doing that.
Of course it wasn't all sunshine and lollipops as the Bears—even without Urlacher—are a tremendous defense.
However, even when the run game faltered for the Vikings, they stayed the course. Each carry and every run was another way to stretch out the game and exhaust the defense.
The fourth quarter is where it paid off quite a bit (though admittedly the game was just about done).
The Vikings were running so much that the Bears had to adjust their base defense to account for the constant run plays, leaving some gaps in the pass defense which even Ponder was able to take advantage of.
Peterson also was able to exploit a tired defense by getting to the edge and turning the corner quicker than they could react.
As you can see in this screenshot, the Bears were so used to Peterson (or by now, Toby Gerhart) running just off-tackle that they were clustering in the middle of the field. They had stopped Peterson multiple times in this manner and assumed with almost 14 minutes left on the clock that the Vikings would keep running up the gut and sapping the clock.
Immediately at the snap, Peterson raced outside, while the vast number of Bears on the line crashed straight ahead.
Some of the defenders react, but not quickly enough to get a good angle on Peterson who turned the corner quickly.
It was only a nice tackle by Conte which kept this from becoming a much longer run. As it is, Peterson made the first down and extended the drive.
Peterson's day, while not the biggest one of his career—or even his year—was a great example of how vital he is to this team.
With a quarterback prone to drive-killing mistakes, the ability to essentially remove him from the equation and rely on a running back is a rare thing.
Few backs in the league could line up against eight and nine men in the box on every down and still put together the day Peterson had.
His ability, with some excellent plays and tremendous blocking, made for a game which cemented Peterson as one the best backs we've ever seen.
Follow me on Twitter at @andrew_garda.