Cowboys sign C Kevin Kowalski, place S Matt Johnson on IR

The Dallas Cowboys added depth to their center position Saturday signing Kevin Kowalski to the roster, Clarence Hill of the Star Telegram is reporting. According to Hill, the move is a sign that center Ryan Cook will not play Sunday against the visiting Cleveland Browns (1 p.m. on CBS).

Cook (6'6, 325), who has been filling in for the injured Phil Costa (ankle), has missed practice all week and was listed as doubtful Friday with a sore knee.

Kowalski will more than likely backup guard Mackenzy Bernadeau (6'4, 320), who's expected to slide over and make his first career start at center. Guard Derrick Dockery (6'6, 325) will play right guard.

To make room for Kowalski, who played 11 games at guard and center last season, the Cowboys (4-5) placed rookie safety Matt Johnson on the injured reserve list.

Johnson, Dallas' fourth-round selection in the 2013 NFL Draft, has been out with a hamstring injury.