TRYING TO determine the primary reason for the Eagles' bad-awful pass defense last year is like trying to find an answer to the old chicken-or-egg question.
Was it the meek pass rush, which recorded just 30 sacks and too often gave opposing quarterbacks enough time to get a mani-pedi let alone find an open receiver?
Or was it the mistake-prone secondary, which managed to turn coverage-blowing into a 16-game art form?
Clearly, there was enough blame to go around for the franchise-record 33 touchdown passes the Eagles gave up, their league-worst 99.6 opponent passer rating and their measly eight interceptions.
But judging from the team's offseason moves, it was apparent that general manager Howie Roseman and new head coach Chip Kelly believed the bulk of the blame for last season's defensive aerial disaster rested with the back four, and it's hard to disagree.
They let one of their two starting cornerbacks, Dominique Rodgers-Cromartie, walk in free agency, and paid the other one, Nnamdi Asomugha, $4 million to take a hike.
Seven of the Eagles' nine free-agent signings were defensive players, and four of those seven were defensive backs - cornerbacks Cary Williams and Bradley Fletcher, and safeties Patrick Chung and Kenny Phillips. At least three of those four figure to be season-opening starters.
"Last year, it was just an unfortunate year for everyone," said safety Kurt Coleman, who allowed 17.3 yards per catch, the fourth-highest average among NFL safeties who were thrown on at least 10 times.
"A lot of people got exposed. A lot of people didn't play as well as they're capable of playing. I'm not going to make any excuses for the way I played last year. It was just one of those years. You've got to learn from it and keep moving."
Coleman and the Eagles' other safety, Nate Allen, both received bottom-10 ratings in coverage from Pro Football Focus last season.
Former Pro Bowlers Asomugha and Rodgers-Cromartie each gave up five touchdowns passes. Opposing quarterbacks completed 66.7 percent of the passes thrown in Asomugha's direction.
"It was a rough year," said Allen, whose poor play led to a late-season benching. "But it was a learning experience. Like they say, what doesn't kill you makes you stronger. It helps you grow as a football player and helps you grow as a man."
Few decisions backfire as completely as Andy Reid's to fire defensive coordinator Juan Castillo six games into last season and replace him with secondary coach Todd Bowles.
The secondary, which had been playing decently under Castillo, took a historical nose dive after Bowles took over and tried to tweak some things on the back end.
Opposing quarterbacks, who had a 69.4 passer rating in the first six games, had a 125.9 rating in the last 10. In those 10 games, the Eagles gave up 26 touchdown passes and had just one interception. I repeat, 26 TD passes, one interception.
The Eagles couldn't get off the field on third down. Opponents converted 32.4 percent of their third downs of 7 yards or more.
Opposing quarterbacks had a 132.3 third-down passer rating in the last 10 games, completing 65.3 percent of their attempts. Forty of 75 third-down passes, or 53.3 percent, resulted in first downs.
Coverage breakdowns became the rule rather than the exception. Every time Asomugha would get beat, he'd turn to Allen or Coleman with a confused, weren't-you-supposed-to-give-me-help look.
"You're going to have miscommunication on certain plays," Allen said after yesterday's OTA at the NovaCare Complex. "There's going to be [coverage] breakdowns. The main thing is limiting them and making as few mental errors as possible. One of the biggest differences between a four-win team and a team that goes to the Super Bowl is the amount of mental errors."
The Eagles' secondary would appear to have nowhere to go but up under Kelly and his defensive coordinator, Bill Davis. But with three and maybe even four new faces expected back there when the season opens, it could take time for them to get on the same page.
Williams started 16 games for the Super Bowl-champion Ravens last year, but he gave up six touchdown passes, which was one more than Asomugha and Rodgers-Cromartie. The Ravens didn't try to re-sign him.
Fletcher, Chung and Phillips all have injury issues. Fletcher has started more than four games just once in four NFL seasons. Chung has missed 12 games the last two years. Phillips played in just seven games last season.
"I think we're coming together pretty well," said Allen, a 2010 second-round pick. "That's what this time is for. Coming out here and getting the chemistry together and learn how each other is rolling in certain coverages and work out all the details."
Coleman has started 27 games the last two seasons. Nobody plays harder, but he's probably better suited to be a backup and core special teams player.
"I believe in myself even when other people don't," he said. "That's what carries me through every adverse situation I deal with.
"The bottom line is you have to make plays. If you don't, they'll bring somebody else in who can. That goes for the new people and the old people that were here."
Allen likes the Eagles' new defensive scheme, which will allow the safeties to focus primarily on the pass and leave most of the responsibility for stopping the run with the front seven.
"It's going to free us up a little more,'' he said. "We can really focus on being pass guys. We're still run guys, obviously. But we're pass first, pass second, and then come up on the run whenever you see it.
"We won't get sucked up as much. We won't have to worry about the play-action as much. You still have to respect it. But you don't have to focus on it as much, because you're a pass guy."
Said Coleman: "The d-line and linebackers are going to take care of a lot of the run situations. That's not to say that the safeties aren't going to be called on to make plays against the run. But we're not going to be the first ones on the scene anymore. That's going to be a big change for us. A good change. It's going to allow us to sit back and read the QB a little more. Be more patient.''
The Eagles will play a 3-4 hybrid under Davis. It will be the first time the Eagles have used a 3-4 as their primary base defense since 1985, when Marion Campbell was the head coach.
"I like this defense," Coleman said. "The offense doesn't know where we're coming from. We've giving a lot of the same looks, but bringing different people every time. Different coverages out of the same look. It's going to be tricky for offenses to pick up in a game situation."
Allen thinks the defense will benefit from playing against Kelly's up-tempo offense.
"We're all in pretty good shape right now,'' he said. "It's a good pace. I like it. Everything is fast. When we get in a game and play against a traditional-style offense, it's going to slow down out there and we'll have all the time in the world out there to think."
The blaring music that Kelly plays during his practices forces his players, both offensive and defensive, to communicate via hand signals. Allen thinks that will help the Eagles avoid many of the coverage screw-ups and miscommunications they experienced last year.
"We're signaling a lot," he said. "That's big. That's how it's going to be in a game. We're not always going to be able to hear each other.
"That makes us go into more detail on our communicating with hand signals, and making sure we look at each other before the snap and make sure everybody's on the same page."
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