Packers' defense must improve this week

The Packers wanted to be the NFC's No. 2 seed in the playoffs and earn a first-round bye. Instead, Green Bay's loss Sunday in Minnesota not only forces the Packers to play next weekend, it also set up a rematch with the Vikings. Handing out grades following the Packers' 37-34 loss to the Vikings: Passing Offense: A- It's difficult to find much blame in Green Bay's passing game. Aaron Rodgers completed 28 of his 40 pass attempts for 365 yards with four touchdown passes and no interceptions, finishing with a passer rating of 131.8. Despite the loss, that is a great day for any NFL quarterback. The negative aspect was the five sacks that were allowed, including one that resulted in a Rodgers fumble. Though Rodgers again, by design, stayed alive in the pocket long enough to cause some of that pressure, the Vikings' defense -- headlined by Everson Griffen's three sacks -- took it to the Packers' offensive line on several key plays. Without Randall Cobb, it was Greg Jennings' turn to take over the game from the wide receiver position. In what was by far the biggest game of Jennings' injury-riddled season, the soon-to-be-free agent had eight catches for 120 yards and two touchdowns. Jordy Nelson, who missed the previous three games with a hamstring injury, also had a nice game with three receptions for 87 yards and a touchdown. James Jones added to his NFL-leading touchdown total and caught six of the seven passes thrown his way for 62 yards.Tight end Jermichael Finley was very productive, finishing with a season-high eight catches for 72 yards. Rushing Offense: B Have the Packers found this year's James Starks? With the emergence of undrafted first-year running back DuJuan Harris, it appears that way. It was in Green Bay's Super Bowl run in 2010 that Starks, a relatively unknown rookie running back, stepped up late in the regular season and helped the team's ground game all the way to the championship. Despite Ryan Grant starting the game and getting the first two carries, it was Harris who got every single handoff after that. Harris finished with 70 yards on 14 carries (5.0 average) and showed off his unique blend of speed and power. Harris was just added to the Packers' active roster on Dec. 1, but with coach Mike McCarthy saying recently that he'd like to go with the hot hand at running back, he seems to have found that. A couple weeks ago, Harris was only on the field on plays in which he'd get the ball, as he was still learning the offensive protection schemes. But now, Harris is seeing action more frequently and has made the most of his opportunities. Rushing Defense: C- Adrian Peterson is a great running back. After falling just nine yards short of Eric Dickerson's all-time rushing record, Peterson has clearly entered the discussion of being one of the best at his position to ever play in the NFL. He's an absolutely dominating force who is a serious threat to break out a huge play every time he touches the ball. However, for the second time this season, Peterson ran all over the Packers' defense. No matter how great a running back is, a defensive unit has to be held accountable for that. The Vikings' game-winning field goal was set up because Peterson, as he did throughout most of the game, broke through the line of scrimmage, escaped a few tacklers and gained big yardage. Peterson finished with 199 yards on 34 carries (5.9 average), which is actually an improvement for Green Bay's defense from the game between these teams on Dec. 2. It was in that first matchup that Peterson had 210 yards on 21 carries (10.0 average). But with just 144 hours separating the end of this game and the beginning of the rematch in Saturday's playoff meeting, the Packers have to find some way to slow down Peterson. Passing Defense: D Peterson is great, so expectations are adjusted accordingly. With Vikings quarterback Christian Ponder, he has been far from great in his two-year NFL career. Therefore, when Ponder throws for 234 yards with three touchdown passes, no interceptions and finishes with a 120.2 passer rating, it's alarming. Ponder's recent turnaround, which began after his miserable performance in Green Bay four weeks ago, is the biggest reason that Minnesota made the playoffs. He was very good in Week 16 in a win over the Houston Texans and was very good again in this game. But that doesn't mean that Ponder, at least at this stage in his career, can't have his weaknesses more easily exploited than what happened Sunday. With Percy Harvin on injured reserve, Ponder doesn't have a go-to receiver. But he distributed the ball evenly to Jarius Wright, Jerome Simpson and Michael Jenkins, and picked apart a Packers secondary that had given him nothing on Dec. 2. It also didn't help that the Packers only picked up one sack, that coming from Clay Matthews in the first quarter. Aside from that, Green Bay didn't get nearly enough pressure on Ponder to force him into the mistakes that he's shown he's prone to make. Special Teams: A- There were several positives for the Packers on special teams. Mason Crosby, who has missed more field goals this season than any NFL kicker, went 2 for 2 in this game. That included a 51-yard make, a range from which Crosby had been 1 for 8 prior to it. If Crosby can regain (or has already regained) his confidence, it came at the perfect time heading into the postseason. Jeremy Ross, a first-year kick and punt returner, took over that role from an injured Cobb in this game and was very good. Ross had three kick returns for 86 yards, including a 44-yard burst to help give the Packers solid field position. Ross also had two punt returns for 41 yards, perhaps showing enough that Cobb can now become a full-time wide receiver and know that Green Bay's return game is still in good shape. Overall: C The Packers wanted to win this game. It wasn't a win-or-the-season-is-over game like it was for the Vikings, but McCarthy made it clear that Green Bay wanted to win and get a first-round playoff bye. But that didn't happen. Now the Packers have a shortened week to get ready for a rematch -- this time at Lambeau Field -- against a Minnesota team that feels pretty good about itself. Green Bay's offense was great, but unless its defense can correct the many issues that directly contributed to this loss, the Packers could be in for a huge challenge from the Vikings on wild-card weekend. Follow Paul Imig on Twitter