Positives of playing Blasi as a defender:
1. He would no longer give the ball away in midfield.
Negatives of playing Blasi as a defender.
1. He would still give the ball away, just only closer to our goal.
2. "What's the offsides trap?"
3. Blasi would actually have to keep the ball LONGER than he would in midfield. Not good.
4. We might as well give Miccoli some pot and steroids, tell him to mark someone, and call the operation a success. At least Fabrizio wouldn't give the ball away as much.
5. We could always change tactics and play Blasi as a Libero...but then somehow he would get caught out of position and give the ball away again.
Seriously, not even Brian Clough would spend time turning Blasi into a defender. It would make more sense to just give Blasi away for nothing than waste time experimenting with him as a defender.