The defender was outstanding for victory over Sampdoria last night.
Sarri enthused afterwards: “He has this great positive energy that he transmits to his teammates and we need to use that at the moment. If you see someone in training who is bursting with energy, you put him on the pitch. Once you realise he is carrying on that attitude during a match situation, you keep him there.
“Demiral is brimming with confidence right now, so it seems only right that he plays."
The coach also had a word for midfielder Adrien Rabiot.
He added: "His qualities are emerging. He was out injured for quite a while, but has improved as these three games have gone on, which means he has not yet expressed himself fully.
“I think his potential is superior to what he's shown so far in his career."