Williams leaves (potential concussion)

OXNARD, Calif. -- Cowboys rookie wide receiver Terrance Williams left Friday's practice and was being tested for a possible concussion.

If Williams, who collided with cornerback Brandon Underwood during a passing drill, fails the baseline test, he will miss the Hall of Fame game against the Miami Dolphins on Sunday. Williams has to be symptom-free for a certain amount of days before being cleared to play. The Cowboys' second preseason game arrives quickly -- Friday, Aug. 9 at Oakland -- and he could miss that game as well.

With Williams missing the last hour of practice, Cole Beasley replaced him as the slot receiver and Dwayne Harris took over as the No. 3 receiver on the depth chart.

Other notes:

*Mackenzy Bernadeau (hamstring) made his practice debut on Friday after missing the first 10 practices. James Hanna (hamstring) and Landon Cohen (scratched cornea) also returned to practice.

*Kevin Kowalski (knee surgery), Ryan Cook (back), Ray Dominguez (shoulder), Nate Livings (knee surgery), Demetress Bell (conditioning), Jermey Parnell (hamstring), Alex Albright (back), Jay Ratliff (hamstring) and Anthony Spencer (knee surgery) missed practice and won't play in the Hall of Fame game.