Guys. I've looked the penalty incident through some times. At first i didnt think it was a penalty either. But the more i look at it, it actually looks like Marhisio tried to lob the ball over the keeper and continue his run. The ball was jumping in a slow pace and while Matri was standing still and had no chance of catching it, Marchisio was at pace.
That should have been a penalty and red card. Because we don't know if it was a shot or a lob for himself. And Castellazzi prevented him that run