Jones may require surgery for the hamstring injury that resulted in his placement on injured reserve Tuesday, Rob Phillips of the Cowboys' official site reports.
After he was inactive for the first two games of the season, Jones played just five defensive snaps for the Cowboys in the Week 3 loss to the Seahawks and picked up an injury along the way. He's technically eligible to return after a minimum of eight weeks, though any surgical procedure might end any possibility of an activation from IR.