Trent Cole loves to get after quarterbacks.

The Eagles defensive end piles up sacks like DeSean Jackson collects touchdowns.

So when Cole was seen chasing after Giants wide receivers on Sunday, it seemed a little unusual and, well, counterproductive.

On one play, he was caught covering New York's Derek Hagan and was beaten for an 11-yard reception. When Cole caught up to the receiver and tackled him, the end jumped up and punched the air.

It was difficult to discern if he was upset because of the play - and the fact that the Giants were about to go ahead, 17-3 - or if he was just ticked that he had to cover a receiver 55 pounds lighter.

"My preference is I like to get sacks. I do. I love to get sacks," Cole said Wednesday. "But they say you've got to do what you've got to do. I'm doing my job and doing what they tell me to do. And the team is calling you to go cover receivers. I feel special."

In the ever-evolving NFL, the days when ends in 4-3 defenses like Reggie White would just pin their ears back and only pass-rush are long gone. With today's more sophisticated blitz packages, ends are sometimes asked to disguise as rushers only to drop back into coverage.

The Eagles have long employed this practice, but second-year defensive coordinator Sean McDermott is a bit of a mad scientist when it comes to designing various blitz schemes. And sometimes that means dropping his best pass rusher in an attempt to free a lane to the quarterback for another defender.

If the Eagles and Cole were generating more pressure - as they were earlier in the season - this nuance might not warrant further examination. But in the last six games, the Eagles have only 11 sacks (1.8 per game) after compiling 24 in the first nine (2.7). Cole, who leads the team with nine sacks, has not recorded one in five of the last six games.

Sacks can sometimes be overrated, as McDermott pointed out last week. He said that opponents had been leaving extra blockers in to help their offensive lines of late. But the pass defense has increasingly had its issues, and that's as much a by-product of the pass rush as it is of the secondary.

"It all starts with the defensive line and the offensive line, and the more pressure you put on the quarterback the better everybody looks," Eagles coach Andy Reid said Monday.

In the last six games, the Eagles have surrendered an average of 243.5 yards and 2.7 touchdowns through the air. In the previous eight games, they gave up 214.1 passing yards and 1.75 touchdowns per game.

"There are times when we need to get coverage sacks and there are times when we would like our D-line to get there," safety Quintin Mikell said. "So it does work both ways. We don't want to have to blitz every time, but also when we do blitz, we have to cover enough on the back end for them to get there."

McDermott was not available for comment. But Eagles defensive end Darryl Tapp, who probably drops back the most in the "Joker" role, explained the tactic behind the blitzes in which ends drop into coverage instead of rush.

"It's kind of subtle, but it really confuses offenses," Tapp said. "They expect defensive linemen to rush, and when you drop, they're surprised. We spend a lot of time working on giving [offenses] a consistent look and not changing our stance so they can't tell when you drop or you rush."

Tapp, who spent his first four seasons in Seattle, said the Eagles use the ploy more than the Seahawks did. He said assistant linebackers coach Mike Caldwell spends time during practice working with the ends on recognizing route combinations and covering receivers.

Tapp, like most ends, would prefer to pass-rush all the time.

"That's what they pay us for," he said. But he had no complaints about his role. Who drops back and who doesn't sometimes depends on what kind of offensive formation the defense will face, and against the Giants that often required Cole to drop back.

"There's stuff that we all have to do on this defense that we don't want to do," Mikell said. "Sometimes I want to blitz. I don't want to [always] have to cover receivers and tight ends, but I have to do what I have to do to win. If someone is upset about that then they have to put that to rest and put the team first."

Contact staff writer Jeff McLane at 215-854-4745 or jmclane@phillynews.com. Follow him on Twitter at www.twitter.com/Jeff_McLane