ARLINGTON, Texas -- Dallas Cowboys starting middle linebacker Rolando McClain will not return for the second half of Sunday's NFC wild-card game against the Detroit Lions with an undisclosed illness.

McClain started Sunday's game but left midway through the second half. He missed the regular-season finale at Washington with an illness but he was expected to participate against the Lions.

McClain has battled knee issues most of the season but has played through it and become one of the Cowboys' leading tacklers.

On the season, McClain led the Cowboys with 10 tackles for loss and was second in tackles (81).