Sakamoto: 49ers’ Hire Jim O’Neil As Defensive Coordinator, Jason Tarver Remains OLBC


The San Francisco 49ers announced today that they have hired former Cleveland Browns DC Jim O’Neil to be the team’s new defensive coordinator. O’Neil, 37, who now takes over for DC Eric Mangini and his 29th ranked defense, will surely have the tough task of rebuilding a unit that was once the backbone of the team.

So what exactly did 49ers HC Chip Kelly see in O’Neil that made him cut ties with Mangini after their meeting? Your guess is as good as mine, but maybe Kelly wanted continuity among his new coaching staff and the hiring of former Browns DBC Jeff Hafley may have played a role.

O’Neil, broke into the NFL coaching ranks as a defensive backs coach with the New York Jets in 2009 before leaving in 2013 to coach the Buffalo Bills linebackers. From there he went on to Cleveland where he would serve as the Browns defensive coordinator from 2014-2015.

So what expectations does Kelly have for his new defensive coordinator? Kelly made it loud and clear in his introductory press conference that ‘situational defense’ will be a point of emphasis under his watch.

“One of the things is we have to be better in situational defense. We have to be able to, on third down, to get them off the field,” Kelly said in his introductory press conference. It’s all about getting off the field and the 49ers defense was tied for 17th in the NFL. This ranking will have to improve dramatically if they hope to climb back atop the NFC West.

Many of the defensive players wanted Mangini to return to San Francisco but that didn’t happen. Let’s just hope that O’Neil can produce a top 5 defense that the Forever Faithful have been longing for since DC Vic Fangio’s departure.

In other news, I’m told that OLBC Jason Tarver will be the only other remaining positional coach from Jim Tomsula’s staff joining RBC Tom Rathman.

HC: Chip Kelly (Eagles/head coach)

OC: Curtis Modkins (Detroit Lions/run game coordinator)
QBC: Ryan Day (Philadelphia Eagles/quarterbacks)
RBC: Tom Rathman (49ers/running backs)
WRC: Bob Bicknell (Philadelphia Eagles/wide receivers)
TEC: Jeff Nixon (Miami Dolphins/running backs)
OLC: Pat Flaherty (N.Y. Giants/offensive line)


DC: Jim O’Neil (Cleveland Browns/defensive coordinator)
DLC: Jerry Azzinaro (Philadelphia Eagles/defensive line)
OLBC: Jason Tarver (49ers/outside linebackers)
ILBC: Hardy Nickerson (Tampa Bay Buccaneers/linebackers)
DBC: Jeff Hafley (Cleveland Browns/secondary)


 STC: Derius Swinton (Chicago Bears/assistant special teams)
Ryan is the Founder/CEO of, 49ers Beat Writer, Live Game Day Correspondent for Bleacher Report and member of Pro Football Writers of America. Born and raised in San Jose, he also graduated from San Diego State University. His work has been featured on NFL Network, 95.7 The Game, National Football Post, Sports Illustrated, FanSided Network, ESPN Radio, CBS Sports 810, and NBC Bay Area News. For more information, please contact him via email at or call him at (408) 622-0996.