Jim Schwartz is key to ending Eagles' search for DBs

The common thread for successful secondaries in the NFL is good coaching and the Eagles hope they have that in Jim Schwartz. Leon Halip/Getty Images

PHILADELPHIA -- Culture may beat scheme, as former Philadelphia Eagles coach Chip Kelly famously said, but scheme is still pretty important -- at least in the defensive secondary.

The Eagles have had a revolving door at safety and cornerback for the past six years. Some of that is a result of bringing in the wrong players. But a fair portion of the responsibility falls to ineffective coaching and flawed defensive schemes.

After the death of defensive coordinator Jim Johnson in 2009, head coach Andy Reid promoted Sean McDermott to run the defense. McDermott was gone after one season. Reid then made the still-unbelievable decision to replace McDermott with longtime offensive line coach Juan Castillo.

Cornerbacks Nnamdi Asomugha and Dominique Rodgers-Cromartie were flops during this era. Both had success elsewhere, but they were major problems in Philadelphia.

When Kelly was hired in 2012, he hired Bill Davis as his defensive coordinator. Kelly was committed to running a 3-4 scheme. In three years, the Eagles brought in cornerbacks Cary Williams, Bradley Fletcher, Nolan Carroll and Byron Maxwell. All except Carroll are now gone.

Their pass defense was terrible, especially the past two seasons.

The Eagles' best chance for improving their pass defense is new coordinator Jim Schwartz's aggressive 4-3 scheme. Like Johnson (and Buddy Ryan before that), Schwartz's priority is disrupting opposing quarterbacks by getting pressure on them. His defensive backs are asked to be on the lookout for errant, rushed passes to intercept.

The question is whether the Eagles have the personnel to execute such a scheme. And the answer is: probably.

The Eagles have added Leodis McKelvin and Ron Brooks, two cornerbacks who played for Schwartz in Buffalo in 2014. They re-signed Carroll this week. That trio will be added to a young group that includes 2015 second-round pick Eric Rowe, sixth-round picks Randall Evans and JaCorey Shepherd, undrafted Denzel Rice, former CFL player Aaron Grymes and 2014 draft pick Jaylen Watkins.

Is that enough? A look at the top secondaries in the NFL is in order here. The bottom line is that it doesn't necessarily take four first-round draft picks to create a good secondary.

The Seattle Seahawks have had the best all-around secondary in recent years. The "Legion of Boom" has a first-round pick in safety Earl Thomas. But the other three starters in the Seahawks' two Super Bowl years were fifth-round picks Richard Sherman and Kam Chancellor and sixth-round pick Byron Maxwell.

Denver had the No. 1 ranked pass defense in the NFL in 2015. The Broncos started two undrafted players, safety Darian Stewart and cornerback Chris Harris, along with first-round pick Aqib Talib and second-round pick T.J. Ward.

Houston's third-ranked pass defense includes three first-round draft picks (Kareem Jackson, Johnathan Joseph and Kevin Johnson. The fourth starter is Quintin Demps, who was a fourth-round pick by the Eagles in 2008. Demps was one of the players who went through the Eagles' revolving door over the last few years.

Another of those, safety Kurt Coleman, was a seventh-round pick in 2010. Coleman now starts in Carolina's secondary. The Panthers led the NFL in interceptions last season. Along with Coleman, the Panthers start cornerback Josh Norman, a fifth-round pick in 2012, and second-round picks Roman Harper and Charles Tillman.

The common thread is solid coaching. That covers the coaching players get on technique as well as the soundness of the defensive scheme. That's obvious from looking at the top secondaries, but also from looking at the Eagles.

Malcolm Jenkins was selected for the Pro Bowl after his second season in Philadelphia. But the list of defensive backs who have been acquired and discarded since 2008 is staggering: Quintin Mikell, Sean Jones, Nate Allen, Dimitri Patterson, Coleman, Asomugha, Rodgers-Cromartie, Jaiquawn Jarrett, Brandon Boykin, Williams, Fletcher, Earl Wolff, Patrick Chung, Walter Thurmond and Maxwell.

That's a recipe for disaster. The first step toward fixing it is bringing young players into a sound defensive system and letting them develop. That's where the Eagles are in 2016.