Earlier, two sources with knowledge of Spencer's condition were optimistic he might be available to play, but he never received final clearance to play Monday.
Spencer missed practice all week with the injury and has been listed as questionable.
Spencer is expected to wear a protective harness, according to the sources.
The sixth-year pro ranks second on the team in both tackles (21) and sacks (2).
UPDATE: Spencer is officially listed as inactive by the Cowboys.
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