Training Camp opened this week in stark contrast to last season. While many of the team's newly signed free agents were forced to watch from the sidelines until the new Collective Bargaining Agreement (CBA) was ratified last year, the only ones watching from the sidelines this week are fans in the bleachers.

But perhaps the most important change is that defensive coordinator Juan Castillo had the chance to work with his entire unit throughout the offseason.

Castillo was named the Eagles' defensive coordinator in February 2011 while the lockout forced teams to close their facilities. In his first year as a defensive coach in the NFL, this meant Castillo was afforded virtually no time with his new players.

Having now spent a full season in charge of the defense, Castillo believes having those offseason programs will make for a much more productive training camp.

"We've had time in the Organized Team Activities (OTAs) to teach our concepts and now take it to the next level in training camp," Castillo said after the team's morning walkthrough Tuesday.

Despite last season's 8-8 finish, Castillo sees silver lining in the way his defense grew throughout the season.

"There's always something positive about everything," Castillo said. "I think we came together at the end as a group; as a team. So now the thing is just to take it to the next level."

That next level is likely to include contributions from several of the rookies in attendance. Several first-year players, including defensive tackle Fletcher Cox and linebacker Mychal Kendricks, will be asked to contribute immediately.

"It's exciting because we have some really good young kids, and some of those young guys have a chance to help us this year," said Castillo. "So really it's exciting but it's also important that we teach our defense so that they can be prepared, with the veteran guys, to help us."

The rookies will be asked to contribute and improve to a defense that ranked in the top 10 in total defense last season. But the improvement Castillo is looking for doesn't necessarily show up in the stat sheet.

"A lot of times, improvement is not numbers," he explained. "Improvement is consistency. The numbers don't always tell the truth."

Fortunately, last year's defensive unit improved both in stats and consistency as the year went on. Though the defense began jelling toward the end of the season, Castillo acknowledged that the unit is ready to prove themselves further this year.

"It's a serious atmosphere," he said. "They're having fun, but they know what's at stake and the job they have to do."

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