Procter started only 13 games in five seasons with the Cowboys. Eleven of those starts came at left guard in 2008 for injured Kyle Kosier, whom Cowboys coach Wade Phillips tabbed Monday as the team's new backup center.
The Cowboys originally signed Procter from the Detroit Lions practice squad in November 2005.
Procter was released Monday, when he wasn't on the official team roster distributed before the start of Dallas' first organized team activities of the offseason.
Kosier has never played center in the pros or college, although he's played every other position on the line. Montrae Holland, the team's only unrestricted free agent, got a new two-year contract this offseason and was expected to take over as the backup.
"You really need a center/guard type if you take them to the game," coach Wade Phillips said. "Kosier could play the backup center and Montrae can go to the game, which he wasn't able to do before. It [makes] us a little stronger in that area as far as who we take to the game and so forth."
The Cowboys also lost backup offensive lineman Duke Preston, who retired Monday.
Information from The Associated Press and ESPNDallas.com's Calvin Watkins was used in this report.