McGary, who exited Sunday's 22-17 loss to the Chiefs early, is believed to have suffered an MCL sprain, Ian Rapoport of NFL Network reports.
McGary will undergo an MRI to verify the diagnosis and also receive a timeframe for his recovery. While he is out of action, the Falcons will be without their starting right tackle and will likely turn to Storm Norton to handle those duties. However, depending on the severity of the sprain, McGary could still suit up this Sunday against the Saints.