It's rare that a game's first play from scrimmage is the most critical, but it sure seemed that way in Minneapolis on Sunday.
Many Bears had a chance to stop or at least slow Adrian Peterson on his 51-yard run.
Defensive end Corey Wootton had excellent penetration on the play but seemed surprised when Christian Ponder handed off. Peterson ran right by him.
Cornerback Kelvin Hayden was the unblocked ninth man in the box but was too slow to attack.
New middle linebacker Nick Roach was blown out by tight end Rhett Ellison. Roach took seven steps backward, creating plenty of running room for Peterson.
And then free safety Chris Conte took a poor angle on Peterson and was late getting to him in the open field.
The heck of it is the Bears did a decent job on Peterson for the other 56 snaps, limiting him to 3.4 yards per carry. They held the best running back the NFL has seen in a long time to 1 yard or less on 34 percent of his rushes (not including two 1-yard touchdown runs).
If Brian Urlacher and Tim Jennings had not been injured, the Bears might have held Peterson to a short gain on the first play from scrimmage as well.
Here is what else we learned upon further review.
Grading key: Grades are between 0 and 10 with 0 being complete failure and 10 being perfect.
Linebackers
Grade: 4.5
Roach failed to stop Peterson on either of his 1-yard touchdown runs, but not many defenders could. He was a little late to the hole on the first, and he lost his footing on the second.
Roach had a nice two-play sequence in the fourth quarter, nailing Peterson for a loss of 3 and then hitting Ponder on a delayed blitz that forced an incompletion.
Lance Briggs was a force in the game with good reads and solid tackles. But he might have prevented a key conversion on third-and-9 on the first drive if he didn't lose his footing in coverage.
Safeties
Grade: 6
Major Wright played with discipline, instinct and toughness. It's difficult for any safety to win against Peterson in the hole, but Wright stopped him twice inside the 5-yard line.
Wright also hung on to a midfield floater from Ponder even though Conte rammed him on the play.
Cornerbacks
Grade: 5
Charles Tillman played his usual physical game, coming up hard and tackling Peterson after a one 1-yard gain in the fourth quarter and forcing a fumble by Peterson.
Hayden did not have a great game in terms of tackling, and he gave up a 10-yard catch to Jenkins on third-and-6 in the fourth quarter that hurt.
Defensive line
Grade: 5.5
There weren't many pass-rush opportunities, but Wootton had some good initial steps and the Bears' only sack of the game. Julius Peppers might have had a sack with a hard inside rush in the second quarter, but he was held by offensive tackle Matt Kalil.
For the most part, the linemen played the run well. There were strong demonstrations of will by Wootton, Peppers, Israel Idonije and Matt Toeaina.
On the third play of the game, Toeaina fought through a double team of John Sullivan and Brandon Fusco, moved laterally and brought down Peterson for a 1-yard gain. Impressive.
Quarterback
Grade: 5
Four of Jay Cutler's passes were too high for their intended targets to catch, including one interception, and another that went in and out of the hands of Vikings safety Jamarca Sanford.
Cutler was not as accurate as usual, but what really did him in were receiver failures. There were four dropped passes in the game, two of which could have been touchdowns.
What Cutler did very well was use his feet. His 11-yard run for a first down was spectacular, as he broke away from defensive tackle Kevin Williams in the backfield and then dragged defensive end Brian Robison 5 yards at the end of the play.
In his only series, Jason Campbell moved the offense efficiently, taking what the Vikings gave him.
Wide receivers
Grade: 4
As magnificent as Brandon Marshall was for most of the game, his fourth-down drop in the fourth quarter was a killer. But his ability to come up with contested catches really stood out.
Alshon Jefferey hurt the Bears as much as he helped them. A savvy route runner would not have been on the ground on that first-quarter play in which Cutler was picked off.
Then in the third quarter he dropped what should have been a 39-yard touchdown pass.
But his second-quarter touchdown catch was very nice. He swam past Josh Robinson to free himself and made an over-the-shoulder catch that a lot of receivers struggle with. In the fourth quarter he pulled in a back-shoulder throw for 30 yards with Robinson all over him.
Tight ends
Grade: 6
Even though there were five passes thrown to Davis that he didn't come up with, this was one of his best games of the season.
Only one of the incompletions was on Davis — a drop of what should have been a reception of more than 20 yards over the middle in the fourth quarter.
Davis was difficult to get down after two of his three catches, and he blocked well.
Running backs
Grade: 7
The Bears didn't hand off to Matt Forte much, but when they did he ran well, making defenders miss and taking advantage of blocks.
He contributed in other areas as well. Forte put in a lot of work as a pass protector and was very solid. He also caught a season-high six passes.
Offensive line
Grade: 4.5
The Bears gave left tackle J'Marcus Webb plenty of help on Jared Allen, and Webb held up well for most of the game. But as he often does, he had a couple of plays that were back-breakers.
He was called for holding Allen twice. On the first, in the second quarter, the penalty accounted for 33 yards because it wiped out a 23-yard completion.
Despite Webb's fourth-quarter chokehold, Allen still hit Cutler, which led to a second hit by Everson Griffen. Cutler apparently was injured on the play.
Right tackle Jonathan Scott also struggled with Robison's speed on a number of snaps.
James Brown played more than half the game at left guard in his first extended playing time. On Forte's 36-yard run, Brown had a key block on a trap on Robison. He also was called for holding and did not work well in tandem with Webb on Allen's inside rushes.
Special teams
Grade: 6
Adam Podlesh dropped four punts inside the 20 and notched a touchback as the emergency kickoff man. Zack Bowman forced a fumble and was responsible for Eric Weems downing a punt at the 1.
Twitter @danpompei
