As we approach the midpoint of a season lacking in clarity, I thought I'd identify some individual units that are separating themselves from the pack, for better or for worse. Below, I've highlighted four units that have been scary good so far -- and four that have been scary bad:
SCARY GOOD
1) Bears' defensive front
Chicago has allowed 300 yards or less in each of its last five games -- a stretch that included three wins, including one each against Ben Roethlisberger and Cam Newton. Holding the Panthers to 293 yards in over 38 minutes in Week 7 was especially impressive. Veteran Akiem Hicks, former second-rounder Eddie Goldman, fast-rising youngster Jonathan Bullard and the steady Mitch Unrein have been central to this effort. Linebackers Leonard Floyd, Danny Trevathan, Pernell McPhee and Christian Jones have been playing very well, also, for the NFL's seventh-best defense.
John Fox wins everywhere he goes, and I can see this defensive front pushing Chicago to the postseason. I don't know if the unit is good enough to ensure a victory once the Bears get there -- you still need strong quarterback play to succeed in the playoffs, and that's a question mark with rookie Mitchell Trubisky under center -- but Floyd and Co. have this team ahead of schedule. One thing is certain: You don't want to look up on offense and see these guys lined up across from you.
2) Jaguars' defensive line
With 33 sacks in seven games, Jacksonville is on pace to finish with a record 75 sacks in 2017. Veteran free agent Calais Campbell appears to have tied everything together this season. Campbell had just 8.0 sacks last year but has 10 already this season, and his presence seems to have influenced former first-round pick Dante Fowler, both on and off the field. With 5.5 sacks, Fowler has already topped his sack total from last season (4.0), while 2016 third-rounder Yannick Ngakoue is on track to nearly double the 8.0 sacks he produced as a rookie. And don't forget about 2016's big free-agent signee, Malik Jackson, who produced seven individual pressures in last Sunday's takedown of the Colts, which was the second-most in the NFL last week, per Next Gen Stats. (Notably, Ngakoue and Campbell each had six pressures, tied for fourth-most, with the team combining to sack Jacoby Brissett 10 times.) Opposing QBs have compiled a passer rating of 62.3, the lowest mark in the league, against the NFL's second-best pass defense. The Jaguars also have a league-high 16 takeaways, including six forced fumbles, though they haven't been great at stopping the run (30th in the NFL in run defense) -- that's this group's Achilles' heel.
Jacksonville's secondary is very good, and that undoubtedly helps boost the pass rush. But the pass rush also helps the secondary. I've been on this team for awhile, so I've obviously been burned by the Jaguars before -- but this year, they seem like a legit playoff contender, thanks largely to the defensive line.
3) Rams' offensive line
The Rams are just 13 points away from surpassing their entire point total from 2016 (224). Sean McVay deserves a lot of credit for Los Angeles' offensive awakening, as do Todd Gurley, Jared Goff and the raft of new receivers -- but the line is playing a huge role. When the Rams signed Andrew Whitworth, they added an athletic left tackle with unbelievable drive and attitude. He's a special human, playing as well as any tackle in the league at 35 years old. Fellow signee John Sullivan has joined with Whitworth and holdovers Rodger Saffold, Jamon Brown and Rob Havenstein to help power the NFL's top scoring offense (and ninth-ranked offense overall).
Last season, Rams quarterbacks were sacked 49 times, second-most in the league, with Goff sacked 26 times in seven games. Through seven games this season, Goff has been sacked 10 times, tied for fourth-least. The line has also helped open things up for Gurley, who is averaging a career-high 89.6 yards per game after putting up 55.3 per game in 2016. It's no coincidence Los Angeles is atop the NFC West with a strong chance to make some postseason noise.
4) Chiefs' pass-catchers
Tyreek Hill has been sensational. Everyone saw the impact he had as a rookie in 2016, when he scored 12 total touchdowns (including rushing, receiving and return scores), but there was some question as to whether the 5-foot-10, 185-pound Hill could step in and be a big-play No. 1 receiver. Well, Hill has been just what the Chiefs needed him to be. He and stud tight end Travis Kelce are tied for the team lead in targets with 49, and Hill has a team-high 515 receiving yards (14.3 per catch) and three touchdowns. Kelce, meanwhile, ranks third in catch percentage (75.5) among players with 45-plus targets this season, while Hill ranks fifth (73.5 percent) -- the Chiefs are the only team with two players ranked in the top 10 of that category, according to Pro Football Reference. The Chiefs are also just one of two teams with two players ranked in the top 15 in receiving yards (Hill is fifth and Kelce is 15th with 423; the other team is the Patriots, courtesy of third-ranked Brandin Cooks and 13th-ranked Rob Gronkowski).
Beyond Hill and Kelce, Demarcus Robinson looks like a real sleeper, while Albert Wilson has stepped up in the wake of Chris Conley's ruptured Achilles. Kansas City boasts the NFL's third-best offense and fifth-best passing attack, with Alex Smith's otherworldly performance (15:0 TD-to-INT ratio, 120.5 passer rating) underscoring the value of a strong pass-catching corps.
SCARY BAD
1) Raiders' secondary
Oakland has spent big money (signing Sean Smith and David Amerson) and serious draft capital (selecting safety Karl Joseph in the first round in 2016 and Gareon Conley in the first round in 2017) on its secondary -- and yet, the unit has been a sieve. Not only are the Raiders the first team in history to go seven games in a season without recording a single interception, but they're allowing opposing quarterbacks to post a league-high passer rating of 109.0, nearly 20 points higher than the team's mark last season (89.9). They've also allowed a 47.8 percent completion rate on deep throws (traveling 20-plus air yards), the second-highest mark in the NFL, and 39 wide-open targets (with 3-plus yards of separation) downfield, the fifth most this season, per Next Gen Stats.
Conley hasn't played much this season, held back by shin splints, while second-round pick Obi Melifonwuhas yet to see the field. Joseph's strength, meanwhile, appears to be as a run-stopping safety. Smith and Amerson, however, just have not played well at all. Amerson must have a neon flashing light on him, because opponents can't wait to target him: So far this season, he's given up 16 catches on 23 targets for 354 yards, three touchdowns and a passer rating of 151.7, per Next Gen Stats. Smith, meanwhile, is no longer starting, but he's been a liability when on the field, allowing 14 catches on 19 targets (73.7 percent) for 230 yards, one score and a passer rating of 131.5.
2) Patriots' secondary
This unit has been so bad that even after last Sunday's encouraging 23-7 win over Atlanta, in which the Falcons were held to 223 passing yards, New England stillranks 32nd in pass defense, with opponents averaging 310 yards per game. The Patriots allowed opposing quarterbacks to top 300 yards in six consecutive games, the first time that's ever happened in NFL history. New England's coverage problems were significant -- consider that the Patriots have allowed 52 wide-open targets downfield (with separation of 3-plus yards) this season, the most in the NFL, according to Next Gen Stats.
Cornerback Malcolm Butler has allowed 26 catches, four scores and a passer rating of 98.2 (with two picks) on 41 targets, while big free-agent acquisitionStephon Gilmore (who returned to practice Wednesday after missing two games with a concussion) has allowed 12 catches on 17 targets. These coverage problems seem to have stemmed from confusion and blown assignments; the defense has just looked out of sync, which is unusual for a Bill Belichick-coached team. We'll see if Sunday's showing -- which included a standout effort from Johnson Bademosi at corner -- marks the beginning of a turnaround for this group.
3) Bengals' offensive line
After ranking 13th on offense in 2016, Cincinnati has plummeted to 29th. Andy Dalton, who is posting a career-high interception rate (4.2 percent) and a passer rating of 83.7, is on pace to be sacked 50 times, while the ground attack has been limited to 81.8 yards per game and 3.3 per carry, despite the presence of Joe Mixon, Giovani Bernard and Jeremy Hill. Dalton is not the kind of quarterback who can successfully overcome protection issues and an ineffective run game. It's hard not to point the finger at Cincinnati's offensive line. After losing Whitworth and Kevin Zeitler in free agency, there was an opportunity for former first-round pick Cedric Ogbuehi and former second-rounder Jake Fisher to step up, but the third-year pros have failed to make their mark. When they drafted Ogbuehi and Fisher, the Bengals surely did not envision having to rotate a well-worn veteran like Andre Smith in with them. Given the collection of skills players in Cincinnati, this offense should be much better -- and I think the O-line is holding the Bengals back.
4) Dolphins' offense
For this team -- which has receivers like Jarvis Landry, DeVante Parker and Kenny Stills, plus Jay Ajayi at running back -- to rank 32nd overall on offense (with 261 yards per game) is a travesty. To me, the blame can be placed on the quarterback play the team has received thus far. Jay Cutler posted a passer rating of 78.8 through six games, with seven touchdowns, five picks and 5.53 yards per attempt. This kind of ineffectiveness would be understandable if the team had no weapons, but that's not the case in Miami. It's to the credit of Adam Gase -- one of the best young coaches in the NFL -- that the Dolphins are 4-2 despite carrying a point differential of -20. I would expect things to turn around with backup Matt Mooreunder center this week, after Cutler cracked his ribs in Week 6. If nothing else, this season should further clarify how much injured quarterback Ryan Tannehill brings to the table.
Also considered: Redskins' receivers, Browns' running backs, Buccaneers' defensive line, Ravens' passing offense.
Follow Gil Brandt on Twitter @Gil_Brandt.