The Chargers signed running back Sony Michel to bolster their depth behind Austin Ekeler.
Recently released by Miami, Michel spent last season with the Rams, rushing for 845 yards and catching 21 passes for another 128 yards.
He was a first-round draft pick of New England in 2018 and spent three years with the Patriots.
The team waived running back Larry Rountree III to make room on their 53-man roster.
Also Wednesday, the Chargers signed the following players to their practice squad: defensive backs Kemon Hall, Michael Jacquet, Raheem Layne and Mark Webb Jr.; wide receivers Michael Bandy, Jason Moore Jr. and Joe Reed; defensive linemen Christian Covington and Joe Gaziano; offensive linemen Zack Bailey and Foster Sarell; edge rusher Carlo Kemp; linebacker Tyreek Maddox-Williams, and tight end Hunter Kampmoyer.