McClain got hurt in the middle of the first quarter during the Packers' first drive. He was ruled out for the game at halftime.
McClain had cleared concussion tests and practiced Friday after missing the first two workouts of the week dealing with symptoms coming out of the win in the wild-card game over Detroit.
While McClain has had a hard time staying on the field late in the season, overall the veteran has been a stabilizing presence for the Cowboys after joining the team late in training camp following a season-ending knee injury to Sean Lee.
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