Eagles' D needs more than just a CB

By now, you know the numbers.

In 2010, the Eagles' defense gave up a franchise-record 31 touchdown passes. Only the Cowboys and Texans allowed more (33 apiece).

And opponents scored on 78.26 percent of their trips inside the red zone against the Eagles. That was by far the worst mark in the NFL. The Texans were second-worst at 67.8 percent.

But it wasn't all bad. The Birds limited opponents to an 80.8 QB rating, which ranked 11th. And the Eagles' 23 interceptions were third-best.

With an (hopeful) eye on free agency, I decided to focus in on those touchdown passes to get a better idea of how teams attacked the Eagles and why opposing offenses had so much success.

Before I get into my findings, I must give reader Mark a big thank you for setting up a spreadsheet for me, which made it pretty easy to chart the touchdowns. The MTC readership came up big once again.

Please note that I did not count the Week 17 touchdown pass against the Cowboys, but I did include the playoff game against the Packers. So overall, we're working with 33 passing touchdowns allowed.

WHO SCORED ON THE EAGLES?

I know, the better question might be: Who didn't?

Here's a chart of how those 33 touchdowns broke down, position-by-position:

The numbers surprised me. We all know the Eagles seem to always have trouble covering opposing tight ends, but 11 touchdowns?

Overall, tight ends and running backs (combined) accounted for more touchdowns in the passing game than opposing wide receivers.

What does this tell me? While the consensus is that the Eagles need to find a right cornerback as soon as the lockout is over, one player is not going to cure all this team's problems against the pass.

Linebacker is a major concern. The Eagles have drafted five LBs in the past two seasons, but the position, for the most part, is an unknown. We don't know how much Jamar Chaney and Keenan Clayton will improve from their rookie years. We don't know if Stewart Bradley is going to be here, if he's capable of staying healthy or if he can play at a consistently high level. And we don't know how NFL-ready rookies Casey Matthews, Brian Rolle and Greg Lloyd will be.

My hunch is that the Eagles will let the young guys battle it out for playing time, but if there's talent to be had in free agnecy, this is the right offseason to make a move.

BURNING THE BLITZ?

Sean McDermott based his defensive philosophy on Jim Johnson's teachings, but teams had plenty of success when the Eagles didn't blitz and only rushed only their four defensive linemen.

On the 33 touchdown passes, only 10 came against an Eagles blitz.

Meanwhile, more often than not, opposing offenses had success scoring on the Eagles without keeping in extra blockers. On only 13 of the 33 touchdowns did the offense use more than their five offensive linemen to protect the quarterback.

On four of the 33 touchdown passes, Eagles rushers outnumbered the offense's blockers, but the Birds didn't get to the quarterback.

TOUCHDOWN TARGETS

Which Eagles were burned the most? This was a difficult one, and I tried to make sure I took an honest look. On eight of the touchdowns, I really couldn't tell. That might mean an offensive player got between two defenders in zone coverage. Or the opponent might have scored on a screen or a quick throw where really the whole defense was at fault.

But for the other passes, I thought I had a pretty good idea of which Eagles defender was responsible in coverage:

It was pretty easy to tell when a cornerback was responsible in coverage. Safety is a very difficult position to track off of TV, but I did my best.

To that end, there were several instances where Nate Allen got to the ball right after a touchdown catch. I did not count those against him in the chart above. Allen showed great potential as a rookie, but after re-watching the touchdowns, it was clear they need improvement from him in pass coverage.

I like Joselio Hanson more than most, but he had his issues, giving up four touchdowns.

If you're wondering why Juqua Parker is listed, he got caught in coverage on a zone blitz against Tony Gonzalez and the Falcons.

WHERE'D THEY LINE UP?

The receivers who caught touchdowns on the Eagles lined up in a variety of places.

The two most common (eight TDs each) were on the left side opposite the Eagles' right cornerback and on the line of scrimmage, where the tight end did damage.

On six occasions, the player who scored was lined up in the backfield. And a receiver lined up on the right side opposite the Eagles' left cornerback caught a TD on six occasions too (although only one of those was against Asante Samuel).

Five of the touchdowns came from the receiver in the slot on the right side.

LEFTOVERS

* The average length of the 33 touchdowns was 16.3 yards. The longest was Jahvid Best's 75-yard catch and run in the Eagles' win over the Lions.

* 25 of the 33 touchdowns were in the red zone. And 19 were within 10 yards of the end zone.

* 12 of the touchdowns were to the quarterback's right; 11 to the middle; and 10 to the left.

* I noticed an interesting trend on play-action passes. Of the first 14 touchdown passes the Eagles allowed, not a single one came on a play-action pass or a fake handoff. But offenses used play-action or a fake handoff to score on 10 of the final 19 touchdown passes the Eagles allowed. Again, linebacker play was a huge issue. They were caught in no man's land on multiple occasions.

* Trading for or signing a right cornerback should be among the first things the Eagles do once the lockout ends. But I'm less convinced now that the secondary is where they will make a major splash.

The defensive problems stemmed from a variety of factors: Lack of pressure from the defensive line, poor linebacker play, a hole at right cornerback and the overall scheme. The Eagles have already addressed a couple of those areas, getting rid of Sean McDermott and drafting safety Jaiquawn Jarrett in the second round. We'll find out in free agency whether they believe their current players can be good enough under Juan Castillo and Jim Washburn or if they think they need to add major pieces on 'D' to make a Super Bowl run.

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