The Steelers signed veteran center Alex Stepanovich on Monday and released defensive end Jordan Reffett. Stepanovich is a six-year veteran who played for the Atlanta Falcons last season. The Steelers are thin at the center position with Justin Hartwig still recovering from a toe injury and Darnell Stapleton recovering from exploratory knee surgery. Stepanovich will back up both Doug Legursky and A.Q. Shipley. Stepanovich will wear number 67.