Now that Juan Castillo has a year of experience as a defensive coordinator under his belt, he can take advantage of the strengths that he had when he first accepted the position a year ago.

First, Castillo has played linebacker at a professional level. He was a linebacker at Texas A&I and in the USFL for the San Antonio Gunslingers. Now that he knows how he wants his scheme to look and understands what works, Castillo can better teach and find roles for players much like he did late in 2011 as he moved Casey Matthews and Keenan Clayton into sub-package roles.

Second, he coached on the offensive side of the ball for the Eagles for 16 seasons. With better knowledge of how to orchestrate a defense, Castillo can apply that as he deconstructs an opposing offense's strengths and weaknesses.

Castillo's defense finished strong in 2011. The Eagles finished with the league's eighth-best defense. In the last four games, all wins, the Eagles allowed just 11.5 points per game - second in the NFL in that timeframe. The defense was also second in the NFL in terms of total yards, third against the pass and seventh in third-down percentage in the last four games. What that showed Castillo is that the message he preached to his players "got across at the end."

Now, Castillo can preach that message all offseason so they can start fast in 2012. But he knows that everything is not rosy just because of the way the team ended the season.

"We've been working hard since the season was over because you know what? (Eagles Chairman/CEO) Mr. (Jeffrey) Lurie said it, it's unacceptable," Castillo said of Lurie's disappointment over the 8-8 season. "It's unacceptable for all of us. Here's what hurts. We held the Giants to 10 points the second time we played them and they're playing in the Super Bowl and we're not."

Head coach Andy Reid explained on Tuesday that he offered former Eagles assistant coach and former Rams head coach Steve Spagnuolo a spot on the coaching staff after he was fired by St. Louis. According to Reid, there was no discussion about titles, but Spagnuolo opted to join the staff of the New Orleans Saints as their defensive coordinator.

Castillo said he was open to the idea of adding Spagnuolo to the defensive staff. Castillo points to Spagnuolo's resume which includes a Super Bowl trophy from his time as defensive coordinator with the Giants.

"There's nothing wrong with having three or four head coaches on the defensive staff," Castillo said.

Looking back at the late, great Jim Johnson's staffs during his tenure as defensive coordinator in Philadelphia, the defensive coaching staffs included Spagnuolo, John Harbaugh, Ron Rivera, and Leslie Frazier, who have at one point or another gone on to become head coaches. The Eagles added another member to the coaching staff with head coaching experience on Monday when Todd Bowles was named secondary coach. Bowles was the assistant head coach/secondary coach in Miami last season and took over as the interim head coach for three games in 2011, winning two of them.

Bowles provides a veteran voice in the staff that will assist Castillo. While Castillo and Bowles did not know each other personally before the announcement Monday, they have mutual friends including Frazier and Hall of Fame cornerback Darrell Green who helped form a mutual respect. Castillo said that the Johnson staffs became a team and that his must now do the same.

"(It's) no different than the whole defense being a team so you can win a championship," Castillo said.

With 2011 in the rear-view mirror and the coaching staff in place to begin the foundation for a successful 2012 campaign, Castillo knows that it's time to get over the hurt and work towards being in the title hunt a year from now.

"We've got to bring a championship to Philadelphia and I have to do the best I can do to make that happen," Castillo said.

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