Those who were looking for the Eagles' first-team defense to dominate the Steelers Thursday night were likely disappointed. But defensive coordinator Juan Castillo isn't worried. Instead, he's focused on improving his squad in time for next Monday's preseason game against New England.

For Castillo, the key to getting his defense ready is simple.

"The fundamentals part which is what we need to improve on," Castillo said. "Part of that is the tackling (and) the third downs. If you get a team in third-and-long then you have to come through. That's why we worked on that (Saturday). It was very important that we had a good practice with that."

Despite consistent pressure on the Steelers' quarterbacks, the defense had a difficult time getting off the field on third down. Pittsburgh's first possession lasted nearly 10 minutes before the defense tightened up and forced the Steelers to settle for a field goal.

Much of that, Castillo said, was the defense shaking off rust.

"The thing is, (the players) haven't played since (last season)," Castillo said. "It is the beginning and the key here is that by the first game of the season those things are not happening. That's why we are working every day ... Football is a muscle memory game. You do it over and over again and then you get it."

Part of this has to do with the nature of preseason. Although he wants to prepare his players for the regular season, Castillo said he also wants to make sure he didn't show his hand too much.

"I think it is hard because we wanted to work on certain coverages and certain fundamentals in that game," Castillo explained. "It is hard to show everything that you are going to do during the season."

That isn't to say the defense's performance was without positives. Castillo saw several good signs, especially from the defensive line.

"The nice thing about the defensive line was that they were getting off of the ball, but what they were doing was when they were rushing they did a pretty decent job of playing the run also," Castillo said. "They played well and our linebackers played decently. We had a couple plays that you would like to have back but we'll get better."

Ultimately, Castillo said that he wants to be judged not by preseason performance, but by his unit's play when the games start counting.

"Preseason is preseason. I think where it starts is game one," he said. "That's when it has to be ready to go ... I think the important thing to understand here is what we are doing in practice. All of these things are a combination and the games. The preparation and the hard work in practice are the key that is going to get us ready for the season."

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