Jesus christ. No one is arguing there is contact, a foul, a yellow. Marchisio's head is turned, he's already concentrated on taking the ball. He's putting his knee up to protect his mid section, the foot follows the knee. He has to suffer the consequences of being careless with his studs, but it's not an intent to injure, which is what a red card is for.
If you want to give reds for this play, there will be 2-3 reds a game every time there is studs above the foot for fuck sake. I don't want to be the guy that says, "you've never played" but come on...