McCarthy named Capers as defensive coordinator Monday afternoon and said the team will switch from a 4-3 defense, which utilizes four down linemen and three linebackers, to Capers' specialty, the 3-4 defense, which uses three linemen and four linebackers.
A news conference with Capers is scheduled for Tuesday morning.
McCarthy said one of the reasons he wants to change the Packers' defensive scheme is the challenges the offensive-minded coach had in trying to game-plan against it.
"From an offensive standpoint, it creates targeting problems," McCarthy said Monday, announcing Capers' hiring after the two reached an agreement in principle Sunday night. "That doesn't mean we won't line up in a four-man front (sometimes). We'll move in and out of both four-man and three-man fronts.
"But it's an excellent run defense (and it) creates pass rush on the quarterback. From an offensive standpoint ... it really cuts the menu of the offense probably in half of what you would normally do (against) a four-man front."
The Packers haven't had the 3-4 as their primary defense since 1991, when coordinator Hank Bullough used it under coach Lindy Infante. When Mike Holmgren arrived in 1992, coordinator Ray Rhodes employed both 3-4 and 4-3 schemes, using Tony Bennett as both a defensive end and right outside linebacker. Upon Fritz Shurmur's arrival in 1994, the Packers switched full-time to a true 4-3 defense and have utilized variations of that scheme ever since.
McCarthy wouldn't confirm that Packers assistant head coach/linebackers coach Winston Moss interviewed for the coordinator job, saying only that Moss would return in his same capacity next season.
"I think this will be an excellent pairing, with Dom Capers and Winston Moss on defense," McCarthy said.
McCarthy said one of his top priorities was hiring someone with defensive coordinator experience, and Capers certainly fits that bill, having broken into the NFL coaching ranks in 1986. While McCarthy preferred a 3-4 defense, he said he didn't rule out staying with a 4-3.
"The 3-4 defense was the primary target, (but) I was still open to the 4-3," McCarthy said.
McCarthy would not say whether he offered the job to someone else before hiring Capers, with whom he did not have a prior relationship.
"We really started from scratch on the telephone," McCarthy said.
During his four-season tenure with Houston, the Texans ranked 16th, 31st, 23rd and 31st in defense. Capers' Jacksonville defenses ranked fourth (1999) and 12th (2000), his Carolina defenses ranked 23rd (1995), 10th ('96), 15th ('97) and 30th ('98), and his Pittsburgh defenses ranked 13th ('92), third ('93) and second ('94).
Meanwhile, McCarthy said it was a "very difficult decision" to fire eight assistant coaches, including Sanders, earlier this month, and that he "put a lot of time and thought" into the decision.
"Really, what it came down to was, I really didn't feel we were headed in the right direction on the defensive side of the ball," McCarthy said. "It was really an evaluation of the last three years. It was a three-year process. I felt a number of things that occurred in Year 1 showed up again in Year 3."
Copyright 2009 by The Associated Press