Jason Williams will be active on Sunday

IRVING -- Jason Williams was the first college player drafted by the Cowboys this spring. Dallas moved out of the second round and got Williams in the third round, 69th overall, out of Western Illinois.

But Williams hasn't been on the field on a consistent basis. Williams sprained his left ankle in the third preseason game vs. San Francisco. He missed the first three games of the season and didn't play until Oct. 4 at Denver. He played the next week at Kansas City but was inactive the next seven games.

With tight end Martellus Bennett out with a concussion, Williams said he will move into the game-day roster on Sunday when the Cowboys face the Chargers.

Bennett's absence leaves a void on special teams so Williams will have to play on all four special team units.

Coach Wade Phillips said Williams had to learn to be a pro and work on his game on and off the field. Williams said study habits and learning how to prioritize his time helped the last seven weeks.

"I feel fresh because I haven't been doing anything," Williams said after practice on Friday. "It's like my first year [in college] all over again."