The 49ers on Saturday once again called on their practice squad for a helping hand.
The club activated two safeties, veteran Johnathan Cyprien and rookie Jared Mayden, to be available to play Sunday against the New England Patriots.
Cyprien and Mayden, an undrafted rookie from Alabama, were needed because the 49ers' starting safeties, Jimmie Ward and Jaquiski Tartt, are out with injuries. Cyprien and Mayden become the 11th and 12th players, respectively, to be called up from the team's 16-player practice squad this season.
The 49ers placed top running back Raheem Mostert on injured reserve due to a high ankle sprain. Mostert leads the 49ers with 303 yards on 51 rushing attempts (5.9 yards per carry average) despite missing the equivalent of three full games with knee and ankle injuries.
On Friday, Shanahan declined to say who would start in place of Ward, who sustained a quadriceps strain in practice late in the week.
Cyprien had a solid training camp but was among the team's final cuts before the start of the regular season. He has far more experience than the combination of the 49ers' expected starting safeties: Marcell Harris and Tarvarius Moore.
Cyprien, 30, started all 70 of the games in which he appeared over his first five seasons with the Jacksonville Jaguars and Tennessee Titans. He missed all of the 2018 season with a torn ACL.
Last year, he played in a total of five games, including one start, in brief stints with the Philadelphia Eagles and Atlanta Falcons.
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Mostert is the latest 49ers player go be placed on injured reserve, which requires at least a three-week absence.
The 49ers on Saturday also placed rookie wide receiver Jauan Jennings on practice-squad injured reserve.
Here is a look at the 49ers' injury situation.
Out vs. Patriots
LB Kwon Alexander (ankle), S Jaquiski Tartt (groin), S Jimmie Ward (quadriceps)
DE Ezekiel Ansah, WR Tavon Austin, DE Nick Bosa, RB Tevin Coleman, DL Dee Ford, C Ben Garland, WR Jalen Hurd, RB Raheem Mostert, LB Mark Nzeocha, TE Jordan Reed, CB Richard Sherman, DE Solomon Thomas, WR Chris Thompson, CB K'Waun Williams
Physically unable to perform
DL Ronald Blair, C Weston Richburg, DL Jullian Taylor