SANTA CLARA -- Nose tackle D.J. Jones is out indefinitely after being placed in the concussion protocol, 49ers coach Kyle Shanahan said Saturday.
"He'll be back sooner than later," Shanahan said.
Jones was sidelined for the final 30 minutes of practice on Thursday and underwent evaluations on Friday for an apparent left shoulder injury.
The 49ers expect Jones to be back in plenty of time for the 49ers' regular-season opener on Sept. 13 against the Arizona Cardinals.
"He landed on it a little bit," Shanahan said of Jones' left shoulder. "We were concerned because he landed on it and went in. We looked at his shoulder, and it would've been totally fine or he would've come to practice the next day.
"But he ended up having a concussion that we found out when we brought him in. We're not exactly sure when it happened, but it's good that we found that out after looking at his shoulder."
Defensive end Nick Bosa also did not practice Saturday, as Shanahan described it as a "maintenance day."
Bosa appeared to be bothered by an upper-leg condition late in Friday's practice.
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49ers' D.J. Jones expected to return from concussion before 2020 opener originally appeared on NBC Sports Bay Area