Warriors coach Mark Jackson announced the injury prior to Tuesday night's victory over the Detroit Pistons, saying that Golden State's other guards "have to step up."
"Guys have to be ready, guys have to step up and embrace the opportunity, and we move forward," Jackson said, according to the San Francisco Chronicle. "It's a credit to our depth and versatility that we'll find a way to still get it done."
Warriors team doctors diagnosed the stress reaction Tuesday, according to Jackson.
Douglas, who has served as the primary backup to star point guard Stephen Curry, has been bothered by pain in his lower leg since the team's trip to China last month. A five-year veteran, Douglas is averaging 6.4 points in seven games this season, his first with Golden State.