As the 49ers’ new defensive coordinator, Eric Mangini does not figure to make wide-sweeping changes with the unit he inherits.
Mangini has not spoken publicly about his vision for the 49ers’ defense, but it appears the 49ers will be sticking with the 3-4 scheme he inherits after four seasons of Vic Fangio running the show.
“My X’s and O’s philosophy are quite simply you build a team to a scheme,” new 49ers coach Jim Tomsula said at his introductory press conference.
And when asked whether the 49ers would keep using a 3-4 approach, the man who acquires the talent, general manager Trent Baalke, said, “Yeah, our personnel is fit for that right now.”
Mangini has primarily run 3-4 schemes in his previous three jobs with New England, the New York Jets and Cleveland Browns. And a person involved in the interview process told CSNBayArea.com that it was his belief the 49ers wanted to maintain continuity by keeping the 3-4 defense.
As Baalke stated, the 49ers are built for a 3-4. Aldon Smith and Aaron Lynch, presumptive starters next season, appear to be better-suited to play base downs at outside linebacker – rather than being hand-in-the-dirt defensive linemen. Ahmad Brooks' future with the team is in doubt due to his scheduled $6.85 million salary.
Of course, the 49ers employ a four-man line roughly 50 percent of the time anyway, as part of their pass-rush package when they go with five or six defensive backs. That means their outside linebackers drop down to play defensive end on passing downs.
But on base downs, the 49ers will need to find three defensive linemen among Glenn Dorsey, Ian Williams, Tank Carradine, Quinton Dial and Tony Jerod-Eddie. It’s not yet known whether Justin Smith will be back for his 15th NFL season, as he contemplates retirement.
The 49ers figure to continue to use two inside linebackers as part of their 3-4 base package. That means Chris Borland, coming off eight impressive starts as a rookie, could return to a backup role and special-teams contributor if Patrick Willis and NaVorro Bowman are back to full strength for the 2015 season.
Willis played in only 5 1/2 games and underwent surgery to correct a chronic toe problem. Bowman missed the entire season with the knee injury he sustained in the NFC Championship game in January 2014. Willis is scheduled to earn $8.315 million next season. Bowman’s scheduled salary is $5.45 million.
The 49ers’ depth at inside linebacker is good with Borland and Michael Wilhoite, a 16-game starter last season, presumably slated for reserve roles.