Hulse missed the defeat at West Brom the previous weekend with a back injury and could be absent again when the Rams travel to Berkshire on Wednesday night.
"Rob has a slight hamstring problem. I think it is related to the back problem that saw him miss the West Brom game," said coach Gary Crosby.
"He just felt it very slightly, so we will see how it settles in the next few days ahead of Reading."
Reading v Derby. Click here to bet.