SANTA CLARA – The 49ers’ lack of depth at inside linebacker makes a conversion to a 4-3 base defense even more unrealistic, according to defensive coordinator Jim O'Neil.
“We’re built to be a 3-4 team,” O’Neil said on Tuesday.
The 49ers have lost inside linebackers NaVorro Bowman and Ray-Ray Armstrong to season-ending injuries. Gerald Hodges, who started the 49ers’ first three games alongside Bowman, has been demoted and rarely plays.
Michael Wilhoite and Nick Bellore have been the starting tandem in the past two weeks, including in Sunday’s 45-16 loss to the Buffalo Bills. The 49ers surrendered 312 yards rushing – the most since allowing a club-worst 324 rushing yards to the Los Angeles Rams.
“We play 4-3 spacing every time we go into our sub-packages,” O’Neil said. “It’s more 3-4 spacing in our base packages. So if you really broke it down, we’re probably 50-50 3-4 versus 4-3 spacing.”
O’Neil later explained to CSNBayArea.com that the team’s outside linebackers, including starters Ahmad Brooks and Aaron Lynch, are trained to be more similar to defensive ends than inside linebackers in the team's base defense.
Therefore, if the 49ers shifted to a 4-3, the more seamless move would be for Brooks and Lynch to become defensive ends.
“We can get some 4-3 spacing stuff with our outside 'backers, but those guys are better on the line of scrimmage nose to nose on tight ends and doing why they were drafted or brought here,” O’Neil said.
“You’re putting three inside 'backers on the field. So you would actually, if you wanted to play 4-3, you would need another inside 'backer.”
One change that might occur, beginning this week against Tampa Bay, is Hodges could see more playing time. After starting the first three games, Hodges has rarely gotten off the sideline.
Said O’Neil of Hodges, “He needs to play more. He does.”