Coach Steve Spagnuolo said Monday that Diggs would have surgery, probably this week, and that the anticipated recovery time is five months. The 32-year-old Diggs had five tackles in Sunday's 19-6 victory at Arizona including one for a loss.
"He's just been a real strong veteran presence in there," Spagnuolo said. "Not real vocal, but I think the guys have a lot of respect for him because of where he's been, what he's done, what he's about, how he works."
David Vobora or Larry Grant could replace Diggs at strong side linebacker. Vobora got his first start of the season against the Cardinals at weakside linebacker and Grant started the first seven games on the weak side.
Another linebacker, Chris Chamberlain, played most of Sunday's 19-6 win over Arizona with an injured right wrist. Spagnuolo said Chamberlain's wrist was not broken but probably would have a cast.