NFL Week 4 injuries: Trevor Siemian appears to have sprained AC joint in shoulder

Early indications are that Denver Broncos quarterback Trevor Siemian suffered an AC joint sprain in his left shoulder, someone with knowledge of the injury told Tom Pelissero of Paste BN Sports.

The person asked to remain anonymous because the extent of the injury had not been made public by the team.

Siemian is scheduled to have more tests on Monday.

One thing working in his favor for an expedited return is the injury occurred to his left, non-throwing shoulder.

In other Week 4 injury news:

- Carolina Panthers quarterback Cam Newton suffered a concussion in Sunday's loss to the Atlanta Falcons, the team confirmed.

- Arizona Cardinals quarterback Carson Palmer also is in the concussion protocol after taking a hard hit in the fourth quarter.

- San Francisco 49ers linebacker NaVorro Bowman was carted off the field with what was described as a non-contact lower-leg injury. He missed all of the 2014 season after suffering a devastating knee injury in the 2013 NFC Championship Game.

- Denver Broncos quarterback Trevor Siemian was carted off with a left shoulder injury.

- Panthers linebacker Thomas Davis suffered a hamstring injury and did not return.

- Washington Redskins linebacker Ryan Kerrigan suffered an elbow injury and did not return. Fellow linebacker Su'a Cravens was evaluated for a concussion.

- Chicago Bears wide receiver Kevin White suffered an ankle injury and did not return.

- New York Jets cornerback Darrelle Revis was sidelined with a thigh injury in the fourth quarter against the Seattle Seahawks.

- Tampa Bay Buccaneers defensive tackle Gerald McCoy suffered a leg injury and was ruled out.

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