1. After losing to the Lions earlier in the season, the Packers really took their game to another level. What adjustments did the Packers make from Week 4 on?
For the first three games of the season, Packers head coach and offensive play caller Mike McCarthy leaned very heavily on his "Zebra" personnel group: one tight end, one running back, two boundary receivers and a slot. While that package puts the team's best offensive playmakers on the field together, McCarthy was using it too much. As a result, opposing defenses were able to more easily decipher what the Packers planned to run. That came to a head in Detroit when the Lions all but shut down their offense.
It's been a different story since then. The very next week against the Chicago Bears, McCarthy utilized bunched receiver sets and heavy backfields to open up the offense. Largely as a result, the Packers rose to the top of the conference in scoring.
But the biggest change wasn't really a coaching adjustment. Aaron Rodgers wasn't playing particularly well during the first three games of the season. He set a career high for underthrown incomplete passes in Week 2 and nearly matched that total against the Lions.
But whatever was causing Rodgers' inaccuracies early in the season seems to have corrected itself. 10 of his 12 games since Detroit have been interception-free, and Rodgers leads the NFL in touchdown-to-interception ratio with 36:5. His improved play has been the catalyst behind the Packers' 11-4 record.
2. In Week 15, the Buffalo Bills beat the Packers and shut down Aaron Rodgers in the process. What led to the Packers' struggles in that game?
It's actually pretty similar to what happened against the Lions in Week 3. The Bills mostly rushed just their front four, leaving the rest of their defense to cover Green Bay's receivers and contain Rodgers' legs. While most teams don't have the personnel to take that approach, Buffalo's Pro Bowl-laden defensive line was able to do enough to frustrate the Packers' offense. Coupled with an off day for Rodgers and seven drops by the receivers, it was enough to earn Buffalo the win.
3. The Lions have the NFL's best run defense by a pretty wide margin. Just how important is Eddie Lacy going to be on Sunday?
As they did in the first matchup, the Lions are going to stick with a two-deep nickel defense most of the game. While the Packers should have an easier time passing on it at Lambeau, how Eddie Lacy and the ground game respond could determine the outcome. In part because of his blocking, Lacy struggled during the first half of the year. The offensive line has improved since, and Lacy has been stellar since the team's Week 9 bye.
Still, as you mentioned, the Lions have an elite run defense. No player has a 100-yard game against them this season. It's not easy to envision that changing Sunday, but Lacy is the best back they've played this season and he's playing very well right now.
4. What are the Packers' biggest strengths and weaknesses right now?
The Packers' biggest strengths are pretty obvious. They possess the league's most dynamic passing attack and have a ground game that ranks in the top 10 in rushing efficiency. Teams that drop more players into coverage usually get gashed by Lacy, and when they adjust Rodgers tends to tear apart their secondary.
But as good as the offense is, opponents have managed to keep it off the field by attacking Green Bay on the ground and shortening the game. The Packers rank in the bottom half of the league in both yards allowed per attempt and total rushing yards. Though they've improved lately -- opponents have averaged just over 3 yards per carry over the last three games -- this is still an area teams can exploit.
5. What one matchup must the Packers win in order to be victorious on Sunday?
The Packers' offensive line has to keep Detroit's front four off of Rodgers. If they can, the Lions will have no choice but to ditch their two-deep looks and send extra pass rushers. Rodgers thrives in those situations, as his league-best passer rating against the blitz attests. However, if the Lions create pressure without blitzing, it's going to be very difficult for Green Bay's passing game to get on track.
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