McGuire cleared waivers and was outrighted to Triple-A Worcester by the Red Sox on Friday, Ian Browne of MLB.com reports.
McGuire was DFA'd by Boston to make room on the roster for the acquisition of catcher Danny Jansen, but the former will stay within the organization. Before being jettisoned from the 40-man roster, McGuire was slashing .209/.280/.295 with three home runs and 18 RBI across 158 major-league plate appearances this season.