In another likely sign that center Ryan Cook won't play against the Cleveland Browns on Sunday, the Cowboys added center Kevin Kowalski to the roster Saturday.
To make room for Kowalski, who began the season on the physically unable to perform list before returning to practice last week, the Cowboys placed rookie safety Matt Johnson on the injured reserve list.
Look for Kowalski to backup Mackenzy Bernadeau at center on Sunday. Bernadeau, who started the first nine games at guard, will start at center because of injures to Cook (knee) and Phil Costa (ankle).
Cook, who started at center the past four games, hasn't practiced all week and is listed as doubtful on the injury report.
With Bernadeau at center, veteran Derrick Dockery will start at right guard.
Kowalski played in 11 games at guard and center as a rookie last season.
The move with Johson was inevitable as he been hobbled by a hamstring injury since training camp. The Cowboys held out hope that rookie fourth-round pick would be able to get healthy and contribute but the clock finally ran out on Johnson.
He is eligible to return in six weeks.
-- Clarence Hill