Cowboys' safety Roy Williams appealed Tuesday the one-game suspension levied because of his third "horse-collar" tackle of the season. Because his case won't be heard until Wednesday, he was able to take part in a walkthrough practice in preparation for Saturday's game against Carolina. Williams' status is a concern because Phillips has to try setting his defense. Dallas (12-2) has clinched a first-round bye but is still vying for the No. 1 seed and home-field advantage in the NFC playoffs.