A league source tells ESPN's Adam Schefter that the injury is expected to sideline Matthews for at least one month. Fox Sports' Jay Glazer reported Monday that Clay Matthews had successful surgery on his thumb. Rapoport reported Tuesday that it's possible the Packers could place Matthews on short-term IR, but the team hopes he's ready to play before eight weeks.
This still is a debilitating loss for a Green Bay team mired in a three-way tie for first place in the NFC North. Matthews is the defense's most disruptive pass rusher as well as a strong run defender.
The Packers will have to hope 2012 first-round draft pick Nick Perry's breakout game against the Lions is a springboard to consistent production versus the Ravens, Browns, Vikings and Bears over the next four weeks.