Houck (back) is scheduled to visit a spine specialist Monday, MLB.com reports.
The upcoming meeting with a back specialist will be the last in a series of appointments for Houck, who was placed on the 15-day injured list Aug. 6. Boston manager Alex Cora believes the club will have a better idea of the right-hander's timetable after the final consultation, and the earliest Houck can return is Aug. 21. While Houck is unavailable, Garrett Whitlock and John Schreiber have picked up save chances.