Coach Kyle Shanahan said Gray (hamstring) is considered day-to-day, Nick Wagoner of ESPN.com reports.
Gray suffered a hamstring injury in the second half of Thursday's 21-13 win over Seattle and didn't return. However, he appears to have avoided a significant injury and could return to action in Week 16. The rookie third-round pick has made 10 appearances this season, securing just one of seven targets for 10 yards across 62 offensive snaps.