The Chicago Bears will open the 2018 regular season against the Green Bay Packers on Sunday Night Football and they could be facing a Packers defense that will be without starting linebacker Jake Ryan.
Ryan, 26, suffered a knee injury in practice on Monday, one that's been described as serious by NFL Network's Ian Rapoport.
Packers coach Mike McCarthy said Ryan is undergoing additional exams.
Ryan started 12 games for Green Bay last season. He registered 81 tackles on the year, including eight tackles in two games against the Bears.
"We have some young players that have showed some promise out there," Packers GM Brian Gutekunst said Tuesday in response to Ryan's injury, "and we'll let them continue to grow into those roles and see what we have. At the same time, we're always behind the scenes preparing for anything."