The San Francisco 49ers have reportedly hired Jim O'Neil as their next defensive coordinator, according to Matt Maiocco of CSN Bay Area. O'Neil served as the Browns defensive coordinator for the past two seasons and now will join newly appointed head coach Chip Kelly.

Outside linebackers coach Jason Tarver was reportedly the in-house favorite to get the position, but he will remain the 49ers' outside linebackers coach, according to Maiocco. The 49ers gave up an average of 24.2 points per game last season, ranking 18 out of the league's 32 teams, and will look to improve under O'Neil and Kelly in 2016.

The 49ers are expected to run the same fast-paced offensive system that Kelly ran with the Philadelphia Eagles, and that sort of system requires a strong defense. Kelly's offense can be explosive, but against dominant defenses, it has struggled and in turn puts more pressure on his defense. The problem with an up tempo offense is that his team will come off the field after quick three and out multiple times, which doesn't allow much rest between series for the 49ers' defense.

O'Neil's defense with the Browns in 2015 struggled, finishing near the bottom of the league in terms of points allowed. Conditioning will be a big factor for 49ers' defense in 2016, and with offenses like the Seattle Seahawks and the Arizona Cardinals in the NFC West, there is plenty of offseason work that San Francisco will look to accomplish prior to the start of the 2016 regular season.