While the tank destroyers were broadly used in their intended role in the Ardennes—being used as a reserve to counter a massed armored attack – there were two significant differences between their use and the original doctrine. Firstly, there was no central strategic reserve—most tank destroyer battalions were assigned to divisions and kept near the front line, rather than massed in the rear. Secondly, the battalions were rarely committed as a whole; as had become common, they were effectively used as local anti-tank assets, with a platoon or a company assigned to an infantry battalion to bolster its defensive strength.