Martinez could start Saturday's matchup with the Mariners if Andrew Cashner (shoulder) is not ready, Jeff Wilson of the Fort Worth Star-Telegram reports.
Cashner is expected to start Saturday's contest after logging five innings in his most recent rehab start, but Martinez seems to be the backup plan in case any extraneous circumstances arise. The 26-year-old will likely fill a long-relief role if he doesn't fill in as a spot starter.