Overview

• The 49ers signed running back Ameer Abdullah, wide receivers Andy Isabella and Marquez Callaway, and quarterback Carter Bradley to one-year deals to bolster depth at skill positions.
• To create roster spots, San Francisco released wide receiver Equanimeous St. Brown and waived offensive lineman Sebastian Gutierrez, wide receiver Malik Knowles and safety Jaylen Mahoney.
• Left guard Ben Bartch was activated off the non-football injury list and immediately stepped into first-team drills.
• Cornerback Deommodore Lenoir (hip), wide receiver Jauan Jennings (calf) and rookie running back Jordan James (knee) were held out of Thursday’s practice with ongoing injury concerns.
• With Brandon Aiyuk still rehabbing a torn ACL, veterans received rest and rookies logging extra reps will carry the workload into Friday’s padded session.