O'Neil was hired by then-49ers head coach Chip Kelly on January 26, 2016. He was not retained when Kyle Shanahan became the head coach in February of 2017. This will be O'Neil's first coaching job since being let go by the 49ers.
Under O'Neil, the 49ers defense was historically bad. It was last in the league in total and rushing yards allowed, last in points allowed, and 19th against the pass.
O'Neil also spent time on the coaching staffs of the Cleveland Browns, Buffalo Bills, and New York Jets.
More San Francisco 49ers News
-
Kyle Shanahan hiring son of 49ers great to coaching staff
San Francisco 49ers head coach Kyle Shanahan is adding a familiar name to his coaching staff. According to Aaron Wilson of KPRC2, the 49ers are hiring Roman Sapolu, the son of franchise great Jesse Sapolu. The elder Sapolu was a four-time Super Bowl champion and two-time Pro... -
49ers defensive assistant expected to join Packers
The mystery surrounding the removal of defensive backs coach Daniel Bullocks from the San Francisco 49ers' official coaching staff page may have been solved. According to Matt Zenitz of CBS Sports, the Green Bay Packers are expected to hire Bullocks for a role on head coach... -
Report: 49ers confirmed to host Mexico City game in 2026
The San Francisco 49ers are reportedly headed back to Mexico City in 2026, something that was previously assumed but not yet confirmed—until now. According to ESPN's John Sutcliffe, the 49ers will serve as the designated home team for a regular-season game at Estadio... -
Chris Simms details where the 49ers must improve this offseason
Despite an injury-plagued 2025 season, the San Francisco 49ers still managed to finish with 12 wins and added a playoff victory over the defending Super Bowl champion Philadelphia Eagles. The roster showed resilience throughout the year, consistently overcoming...