Reed sprained his big toe in the weeks leading up to training camp. Because it was still bothering him, the Redskins placed him on the physically unable to perform list.
Redskins coach Jay Gruden said they'll re-evaluate him in four or five days and that his stay on the list might be for only a week.
"It's not a significant injury," Gruden said. "We just want to make sure we get him right."
Gruden said Reed looked "so good" in the mandatory minicamp in June and was in excellent shape. Reed is the centerpiece of the Redskins' passing attack, so they want to make sure he's healthy to open the season. Reed has missed a combined 20 games in his first four seasons.
Quarterback Kirk Cousins has a 121.4 passer rating when targeting Reed the past two seasons.
But the focus will be on getting Reed right. As Gruden said, Reed puts a lot of stress on his toes and ankles with how hard he cuts in and out of breaks.
They want to make sure he's fully healed before sending him back on the field.
"Better safe than sorry with a guy like that," Gruden said.