Superb attitude, he was excellent today.
I'm all for keeping him if he keeps it up. He knows the new system, his attitude is great, his movement is excellent, he is a top finisher and I think he can form an interesting partnership with Ronaldo. Outside Kean he is the only striker who really tries to get in behind.
The big argument to sell him is to cash in while we can. But it doesn't seem like we are going to make a gain on him and are likely to blow the cash on Icardi (who I think is far less suited to what we need/has issues). Seeing as he wants to stay we should see if he will compromise on his salary.
As much as I really like Mandzukic, I think under Sarri he may be the better option to sell.