Sunday's performance in Minnesota was the worst the Eagles defense had put forth since Week 4. The 48 points allowed to the Vikings cast a bit of a damper on what the defense has accomplished over the past nine games. The pass rush was largely ineffective, coverage was too loose at every level of the field and players lost their composure due to frustration. Still, the Eagles found themselves in the game after scoring two quick touchdowns.

The defense had a chance to make a key stop at the start of the third quarter to get the ball back to the Eagles offense. Unfortunately, as was the case most of the afternoon, they were unsuccessful.

"I think all of us realized that going into that four quarter, we did not play our best game up to that point," defensive coordinator Bill Davis said Tuesday. "But, even having not played our best game, (early) in that fourth quarter – I believe it was the third-and-14 (on the drive where the Vikings scored the touchdown to go up 34-22) – we still had an opportunity to make plays and turn that game to where we could win it even though we weren't playing at our best. We had a couple things go wrong and multiple people lost their composure. I wasn't the most composed in the box, either, as it was starting to unravel. All of us had a lesson to learn there that the game is tight in the NFL, adversity hits and you've got to be able to overcome adversity and handle it. I think, collectively, we all learned that we can do better and have to better, or bad things happen in the fourth quarter. We gave up 21 points in the fourth quarter when we shouldn't have, and part of it was the composure."

In addition to missing opportunities to force turnovers, get off the field and giving up those 21 points in the fourth quarter, the defense broke down and uncharacteristically gave up a number of big plays in passing game, which Davis pointed to as the main culprit for the overall woes. The defense had been very successful in preventing pass plays over the top all season, but the Vikings were able to find openings and make a number of impressive individual plays. Those coverage breakdowns were exacerbated by some sloppy tackling, as well.

"We gave up way too many big plays – 'x' plays," Davis said. "I believe there were six 'x' plays of over 20 (yards). Now, if I'm not mistaken, three of them were thrown for 20-plus yards, and we did not make those plays. The others were thrown under 20 yards and we missed tackles, so they became big plays. There were two pass interference calls, and we really haven't been getting a lot of those called against us (recently). They were good calls, we did interfere and it put them all the way down inside the goal line. We did not take care of taking the big pass (away) like we had been, and we only had one turnover, whereas in the past we were having a couple more. The biggest part of that game, the disappointment was the big plays both through missed tackles and (coverage)."

Now, in every game, even when the stats don't reflect it, there are mistakes made on defense. It's just a matter of whether the offense is able to exploit them and take advantage. The Vikings were able to do so, and now Davis and his charges must go back to the drawing board and figure out ways to tighten things up so the defense can get back to playing at the level it had showed over the previous nine games.

"The one thing I know is I have never coached in a game where we didn't have multiple errors,
 Davis said. "I don't think anybody has, it just doesn't happen. There are always little things that you have to tighten up and get better. When you lose, a lot of times those mistakes you do make, (the opponent) found. Sometimes they don't find them and you win. The mistakes are always there, you always have to correct them, you always have to tighten it up. The beautiful part of the NFL is every week you can either dominate or be dominated, and most (games) are coming down to the fourth quarter, the end of it, and you have to be really tight in your coverage and your assignment and doing your job. The teams that are a little crisper in their assignments and make less mistakes win."

Up next for this defense as it seeks redemption is the most challenging matchup it will face since, well, the loss to the Broncos. The Chicago Bears have perhaps the league's best wide receiver tandem with the big, physical duo of Brandon Marshall and Alshon Jeffery, one of the game's most complete running backs in Matt Forte and a quarterback in Jay Cutler who can make every throw and has had major success against the Eagles.

"Chicago might be one of the most talented offenses we face," Davis said. "They're in the top five in scoring. They have the big, physical Pro Bowl receivers – two of them (Marshall and Jeffery). They have a tight end (Martellus Bennett) who's an athletic pass receiver – he's very versatile, he's very big. The running back (Forte) is as rounded as any running back we've faced; his pass protection is great, he runs the ball well, he catches out of the backfield well. The offensive line is young on one side, but it's getting better and better. The quarterback (Cutler) can make all the throws and you can tell he understands this offense because his eyes are downfield and he's getting the ball where it needs to be. This is, overall, probably our biggest test."

A lot of things went wrong for the defense against the Vikings, and it showed that the unit still has a ways to go in its quest to be among the best in the NFL. There is not time to dwell on the loss, however. The mindset in defeat for this team is the same as in victory – it's on to the next game, with the focus of getting better and going 1-0.

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