Robinson (hamstring) was placed on injured reserve Saturday, Marc Raimondi of ESPN.com reports.
Robinson already has missed two games due to a lingering hamstring injury and now must miss at least the next four outings, meaning his next chance for game action is Sunday, Dec. 13 at Cleveland. In a corresponding move, the Falcons are signing Khalil Herbert from the practice squad to the active roster to continue serving as the No. 2 RB behind workhorse Bijan Robinson.