Mac Jones quietly is having an outstanding training camp. Through five practices, he has completed a whopping 77 percent of his throws.

Early indications are Pinnock, 26, will step in as a starting safety when the 49ers open the regular season on Sept. 7 in Seattle. With Malik Mustapha sidelined while rehabbing an ACL tear, Pinnock and third-year player Ji’Ayir Brown are running with the first team.

Niners quarterback Brock Purdy was also back at practice Sunday after missing a session on Friday for personal reasons. Pearsall had been out since injuring his hamstring during the offseason program.