GREEN BAY, Wis. — Defensive lineman Muhammad Wilkerson underwent surgery on his left ankle after the Green Bay Packers' loss at Washington on Sunday and will be lost for the season.

The surgery was performed in the Washington area and Packers coach Mike McCarthy said Monday that Wilkerson's injury was "significant."

Wilkerson's foot was trapped under another player while blocking, and he was carted off the field with his hands covering his facemask.

Signed as a free agent for one season and $8 million, Wilkerson, 29, is one of several Packers with major injuries.

"We're beat up coming out of the game," McCarthy said. "You look at the course of these first three weeks, they're battling like hell. We're going to have to see how it sorts out. (The injury report) will be part of our game planning."