Diaz (hamstring) is out of the lineup for Sunday's game against the Red Sox, Chandler Rome of the Houston Chronicle reports.
The Astros have classified Diaz's hamstring strain as a minor one, but the injury will nonetheless keep him on the bench for a second straight contest. Yuli Gurriel will receive the start at second base with Diaz considered day-to-day and Jose Altuve (hamstring) still stuck on the injured list.