The 49ers on Sunday re-signed safety Antone Exum to a one-year contract to fill the roster spot that opened with defensive lineman Kentavious Street being placed on injured reserve.
Street underwent arthroscopic knee surgery Friday. He is eligible to return to the active roster after eight weeks. Only players who were on the initial 53-man roster are eligible for a return off the injured reserve list during the season.
Street sustained a torn ACL during a pre-draft workout with the New York Giants in the spring of 2018. The 49ers still selected him in the fourth round of the draft. He spent his entire rookie season on the non-football injury list.
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The return to Exum gives the 49ers a fourth safety to open the season, joining Jaquiski Tartt, Jimmie Ward and Tarvarius Moore.
Exum appeared in 15 games last season with seven starts. He recorded one of the 49ers’ two interceptions on the season and was responsible for the team’s only defensive score with his return of a Philip Rivers interception in Week 4.