GREEN BAY, Wis. -- If Dom Capers' defensive system can be boiled down to a basic principal, it's this: Blitz as often as necessary to disrupt the rhythm and timing of an opponent's offense.

So it should come as no surprise that since he came to Green Bay as defensive coordinator in 2009, the Green Bay Packers have ranked as one of the NFL's most frequent blitz teams (see accompanying chart).

But there's much more that goes into it than just turning linebackers, safeties and cornerbacks loose.

Some of Capers' best defenses in Green Bay have been those that have blitzed the least (see 2009 and 2010).

"I'd say we're probably normally [blitzing at] around 38 to 40 percent of the time," Capers said.

But with worst defense he fielded, the 2011 unit that ranked last in the league, he blitzed the most.

"We couldn't get any pressure on the quarterback that year," Capers said.

That trend is hardly universal.

Take this season, for example. One of the best defensive performances came in Week 5 against the Minnesota Vikings. In the Packers' 42-10 victory, Capers blitzed on 47.2 percent of the Vikings’ dropbacks, according to ESPN Stats & Information (which defines a blitz as sending five or more pass-rushers at the quarterback). Only three other times this season has Capers blitzed at a higher rate -- at Miami in Week 6 (53.1 percent), against Carolina in Week 7 (50 percent) and against the New York Jets in Week 2 (47.3 percent). All were victories

Then there was 19-7 loss against the Detroit Lions in Week 2, when the defense allowed just 10 points. Capers blitzed a season-low 12.8 percent of the time.

This season, the Packers' defense ranks just 25th in yards, but second in takeaways (22), tied for eighth in Total QBR (50.4) and 11th in sack percentage (7.0).

Here is a look at the Capers' philosophy through the eyes of some of his coaches and players:

Offensive coordinator Tom Clements

Before they were on the same side, Clements coached against Capers. One game stands out: Dec. 8, 2002 in Pittsburgh. Clements was the Steelers' quarterbacks coach, and Capers was the Houston Texans head coach.

"That was a weird game," Clements said. "Our defense held them to about a total of 60 yards. We had about 400 yards, and they beat us by three touchdowns."

Actually, the numbers were these: The Steelers had 422 yards and the Texans had 47. Houston's defense scored three times, two interception returns and a recovered fumble return, in a 24-6 upset.

Which goes to show that when preparing for a Capers' defense, anything is possible.

"Multiple looks, multiple pressures," Clements said. "It requires a lot of film study by the coaches and the players, because you never know what you’re going to get."

Defensive line coach Mike Trgovac

Trgovac, the Panthers defensive coordinator from 2003-2008, knows what it's like to call plays.

He says it's an oversimplification to simply call Capers a blitzer.

"Just to call 100 blitzes, when you start getting in that rhythm of the game, that's actually the easiest part of the game to call," Trgovac said. "The hard part is trying to pick the blitzes based on what you're seeing in the game. You have something set in your mind early and have to adjust from there."

Trgovac says he often finds Capers alone in his office or a film room calling a mock game to try to anticipate those situations.

"He puts in the hours that's required to have knowledge to make a play call," Trgovac said.

Cornerbacks coach Joe Whitt

Whitt, who like Trgovac has been with Capers since 2009 in Green Bay, also says it's unfair to label their defense as just a blitzing scheme.

"I wouldn't say that," Whitt said. "I would say it's a week-to-week deal, but we're going to try to do anything we can to win that week. If we have to bring five or six guys, we will."

But then Whitt pointed to one of the biggest defensive plays in last Sunday's win against the Eagles, Julius Peppers' 52-yard interception return for a touchdown. Capers rushed only three players -- defensive linemen Datone Jones, Josh Boyd and Mike Neal -- and dropped Peppers, Clay Matthews and A.J. Hawk into coverage.

"It's whatever's needed," Whitt said.

Outside linebacker Peppers

The 13-year NFL veteran has never been used like this. In his eight seasons in Carolina and four in Chicago, he more or less had one job: put his hand on the ground and rush the quarterback as a defensive end.

"They wanted me to rush for the majority of the time," Pepper said. "Every now and then there was a fire-zone call where I was dropping, but primarily I was rushing."

Perhaps said that's why Eagles coach Chip Kelly said they weren't expecting Peppers to drop into coverage. He said it was "a great call" by Capers.

"I don't think it's anything new," said Peppers, who leads the Packers with 5.0 sacks and is tied for second on the team with two interceptions. "He's been doing that since he's been here as far as I'm concerned."