A tensioning device and method for post-tensioning a concrete member having at least one crack is provided. The tensioning device may include an elongated body, a stitch catch arm and an anchor. The catch arm may be perpendicularly joined to one end of the elongated body, wherein the catch arm is inserted into a hole in the concrete member. The elongated body may form an anchor recess therein, wherein an anchor interface surface is defined by the anchor recess. The anchor interface may form an anchor aperture for receiving the anchor. The thickness of the anchor interface may uniformly decrease as the anchor interface extends toward the catch arm end of the anchor recess so that when ratcheting the anchor into the concrete member and onto the anchor interface a portion of the applied compressive force and/or torque may be transformed into an axial force along the elongated body so as to provide post-tensioning through the tensioning device and across the at least one crack.