Jalen Mills and Ronald Darby have both given up big plays this year. It's no secret. We've all seen it. When you're a cornerback, there's nowhere to hide.
What's much less obvious and just as important is that Mills and Darby have also very quietly become one of the league's best cornerback tandems in the red zone, which gives them the ability to make up for many of their mistakes between the 20s.
The Eagles are the NFL's best red-zone team after six weeks, and Mills and Darby - with a combined eight pass breakups inside the 20 - are one of the big reasons why.
Let's take a look at some numbers.
Here are the top five red-zone defenses in the league as measured by points allowed per red-zone drive:
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1. Dolphins 3.43
2. Eagles 3.62
3. Vikings 3.91
4. Titans 3.94
5. Ravens 4.17
And the top five red-zone defenses in the league in terms of yards allowed per pass play:
1. Jaguars 1.04
2. Giants 1.33
3. Titans 1.41
4. Eagles 1.44
5. Broncos 1.65
In terms of touchdown percentage, the Eagles are No. 1 in the red zone, allowing seven TDs on 21 drives, and in terms of yards per play in the red zone, they're also No. 1, allowing just 1.65 yards per play.
Inside the 5-yard line, teams are averaging negative-.27 yards per pass play against the Eagles.
That's going backwards.
And in the middle of all of it are Mills and Darby.
Much maligned by fans, both have been very good where it matters the most.
Mills, in particular, has been a weapon, with four PBUs inside the 5-yard-line. Only three other players leaguewide have more than one.
"We put a lot of emphasis as a defense on red zone," Malcolm Jenkins said. "We don't help our corners at all in the red zone, and we bank on them using great technique.
"It's a huge part of what we do on defense, and we'll continue to put pressure on those guys to … play that way."
Opposing quarterbacks are completing just 40 percent of their passes against the Eagles in the red zone, the third-lowest figure in the league.
To excel in the red zone, you need corners who are confident, physical and aggressive, and the Eagles certainly have that.
Both have the discipline to keep their eyes on the quarterback, which is crucial in close quarters because the ball arrives so fast.
Mills leads the NFL with six pass breakups inside the 20, including touchdown-saving plays on Julio Jones, Adam Thielen and Odell Beckham Jr. Darby has two pass breakups inside the 20.
The Eagles have allowed eight TD passes in six games, sixth-fewest in the league.
What goes into the success Mills and Darby have had inside the 20? Defensive backs coach Cory Undlin spoke about that this week:
"They take a lot of pride down there. We've been going in the red zone since we've been here, and we take a lot of pride in that and they're both competitive guys. They study hard, and you've got to play with great technique down there or it's not good. I think they just have a lot of confidence in it and believe in the scheme and they go out there and do everything they possibly can and make sure the ball doesn't get caught on them. They have not been perfect at all, but normally when we get down there, we feel pretty good about the ball not getting caught on them."
The Eagles will certainly have their hands full Sunday at the Linc when they face the Panthers.
Cam Newton is quite a weapon down near the goal-line. His 115.7 passer rating in the red zone is second-best in the league, behind only Kirk Cousins, and his three red-zone TD runs are eighth-most in the league.
"Just staying aggressive, that's the key," Darby said. "Being aggressive and not being afraid to make mistakes. It's all confidence down there and go out and compete.
"They drive down the field and even if they get the ball on the 20, hold them to three points or no points, and we feel like it's a huge turnaround in the game."
Six games into the season, the Eagles' defense is 12th in the NFL in yards allowed and 17th in yards per play.
Yet they're No. 5 in points allowed.
What does that tell you?
They're making mistakes between the 20s and making up for them inside the 20.
It's a dangerous way of going about your business, but so far it's working.
"As a defense, we take a lot of pride in red zone," Mills said. "If they don't score, they don't win. That's the mindset of our defense."
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