Mangini held the job on Jim Tomsula's staff last season. He, along with Mike Vrabel, were interviewed for the position on Kelly's staff. Vrabel turned down the 49ers to remain the linebackers coach with the Houston Texans.
The 49ers defense has a lot of room for improvement. In 2015 under Mangini, the unit finished 18th in points allowed, 29th in total yards allowed, 27th in passing yards allowed, and 29th in rushing yards allowed.
Linebackers coach Jason Tarver, who remains employed by the 49ers, remains a candidate for the job along with Baltimore Ravens linebackers coach Don Martindale. Tarver has been the defensive coordinator for the Oakland Raiders while Martindale was a defensive coordinator for the Denver Broncos.
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