Gore is with the Padres as a member of the taxi squad for Tuesday's game against the Giants, AJ Cassavell of MLB.com reports.
Blake Snell (groin) was scratched from his start Sunday and is attempting to avoid the injured list, though Gore is now with the team on the taxi squad and waiting in the wings to step into the starting rotation. Gore won't officially be added to the big-league roster until Snell's status is determined, but for now the young lefty lines up to potentially make his major-league debut Friday versus Atlanta.