New England Patriots: -17 sack differential (29th in NFL)
The Patriots have been one of the best teams in the NFL this season with a couple of caveats. Number one, and maybe most concerning, they have a -17 sack differential, which is the 4th-worst number in the league at this point.
Why does that matter in the postseason? Well, if you're giving up sacks and can't get the opposing quarterback to the ground, it's going to be a major disadvantage at this time of year. Especially because the Patriots have played the "easiest" schedule in the league this year and haven't had to play from behind a ton.
Philadelphia Eagles: 29.2 three-and-out percentage (32nd in NFL)
There is no question that the Eagles' offense could be their downfall this postseason. Although they're the reigning Super Bowl champions and have the ability to win games any type of way, their offense has been horrendous this season.
The highest three-and-out percentage of any team in the NFL over the course of a season is not a slump, it's an identity. The Eagles just haven't had the consistency offensively to be considered a true repeat candidate. But maybe they can flip a switch in January.
Jacksonville Jaguars: 125 penalties (32nd in NFL)
Ultimately, the Jacksonville Jaguars' biggest downfall could be their lack of fundamental discipline. The Jaguars lead the NFL in penalties this season, so despite their current impressive winning streak, and despite the fact that they are one of the hottest teams in the NFL, penalties can be hard to overcome.
Especially for repeat offenders. When you are the most-penalized team in the league, you are going to be under a different microscope. Fair or not. The Jaguars have to play as clean as possible and be prepared to have to overcome these penalties, or they'll have a quick playoff exit.