Stallard was sent off for an off the ball incident with Marc Joseph, which saw the Millers man go down holding his shin.
Stallard will now miss the home game with Wycombe Wanderers and away ties with Notts County and Chesterfield.
Many of the home fans were bemused with the decision which very few saw, but the red card was brandished and Stllard, who had just regained his first team spot, will now miss out giving Ben Wright another chance to stake a claim for a starting spot.