San Francisco 49ers rookie linebacker Reuben Foster was listed as limited for Thursday’s joint practice with the Denver Broncos. According to Matt Barrows of the Sacramento Bee, Foster is dealing with a “mild AC joint sprain in his right shoulder.”
Though this is a different specific injury than the one that scared many NFL teams away from drafting Foster in April, the 49ers have to be at least a little bit concerned. Apparently, Foster is not worried about this injury, though.
 “I talked to him and like Reuben, big smile, said, ‘I’m straight.’ And, so he’s good. He’s straight,” general manager John Lynch said, per Cam Inman of the San Jose Mercury News.
Foster underwent surgery to repair a torn rotator cuff this past winter. There were reports that another surgery might be needed after the first one didn’t take. It’s also worth pointing out that head coach Kyle Shanahan even said the rookie linebacker might — in a worst-case scenario — be forced to miss some of the 2017 season.
None of that stopped the 49ers from trading back up into the first round to land Foster with the No. 31 overall pick. And he did end up being ready to participate in full this summer during training camp. The 49ers recently elevated Foster into the starting lineup after free-agent acquisition Malcolm Smith was lost for the season. He’s been lighting it up in practice and showed some flashes of greatness in his first NFL game last week.
Blessed with sideline-to-sideline speed, excellent instincts and a willingness to lay people out, he’s the top inside linebacker from the 2017 NFL Draft class. So the 49ers will definitely be in some trouble if Foster’s injury ends up being more serious than the team is letting on right now. With that in mind, don’t be surprised if the rookie ends up sitting out the team’s second preseason game against the Denver Broncos.