Roman Legionaries Vs. Medieval Heavy infantry

[LCorneliusScaeva]

was a question that occured to me the other day, If the romans were to have fought later in history againist full armoured Knights etc. what would have been the outcome? in terms of their weapons, armor and tactics, sure the romans were heavily armored in their day but would they have been able to withstand an army of men who are fully armored?

Just a point for discussion, not sure if this has been discussed or thought about before

I would think the Roman balista and scorpions, if deployed properly, would make short work of the Medieval Knights. In the end, it always comes down to generalship. A good general, knowing he would face heavy cavalry, would prepare for them by chosing good ground, bringing plenty of field artillary, and training his infantry how to receive charges, etc. Didn't Arrian have something to say about how to deal with heavy cav?