No. 4: Myles Hartsfield (free agent)
Tayler Hawkins is the only safety the 49ers currently have on their practice squad, but they could opt for a reunion with a player who was vying for one of those 53-man roster spots last offseason, defensive back Myles Hartsfield.
Hartsfield was a hand-picked offseason free-agent addition by defensive coordinator Steve Wilks, who wanted to bring the 26 year old over from the Carolina Panthers. Yet it was a bit of a shock when Hartsfield ultimately failed to make the 53-man roster despite having an ally in Wilks, although one could argue he, too, was a victim of the numbers game.
Still, provided Hartsfield has kept himself in shape after sitting out from play since roster cuts, it'd likely be an easy addition on the cheap.
And there'd be the added bonus of Hartsfield already knowing Wilks' defensive tendencies and having a small amount of chemistry with others on the Niners defense.