Allen and Warren got one-year deals.
Allen returned to the Steelers during Week 6 last season after being released by Dallas. In 17 games last season with Pittsburgh and Dallas, he had 42 tackles, two interceptions, a forced fumble and a fumble recovery. Allen spent the 2010-12 seasons with Pittsburgh. He was originally selected by Tampa Bay in the fourth round (111th overall) of the 2004 draft.
Warren has spent his entire career with the Steelers since signing as an undrafted rookie free agent out of North Carolina in 2005. Warren has been the team's long-snapper in 133 regular-season games and nine postseason matches. He has played in 64 consecutive regular-season games.
The versatile Wallace got a three-year contract. He played in nine games for the Steelers last season at both guard and center, with four starts. He started the final four games of the season at center.
Wallace signed with Pittsburgh before the 2013 regular season after being released by Tampa Bay. He was originally drafted in the fourth round (107th overall) in 2008 by San Francisco. He's also been on the practice squads of the Detroit Lions, New York Jets and Houston Texans during the 2010-11 seasons.
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