Where does this unhappy player thing come from?
Just because Chelsea are in for him and he would be prepared to move if City wanted to sell him in no way makes him unhappy.
Unhappy is what is going on at Old Trafford and posters should see the difference.
A better way of putting it, perhaps, is that he wants more game time. Which would be legitimate. I'd say that he proved towards the end of last season that he's good enough to feature in league games. Not, certainly, as an automatic starter. But then, if it were down to me, the only automatic starter of the four of them would be an entirely fit Diaz. Based on the past five seasons or so, we can reasonably expect to go deep into three cup competitions as well.
We
need four genuine central defenders, whoever they are. It's not a luxury. Unless City have someone quality lined up, I'd say it would be downright stupid to let Aké go to Chelsea, the more so if Sterling is off there as well. You're strengthening a direct rival considerably.
Oh, incidentally: Rudiger left on a free. Chelsea are linked with Raheem and Raphinha. I know it's all rumour, rumour, rumour (including this one involving Aké), but
if those two were to happen, you're looking at a cool £100 million right there, realistically, possibly more. Where do they get the money? Yes, they've got Lukaku off their wage bill. That helps. You'd expect Werner and Ziyech to be out the door, but they're not going to get a lot for them.
I admit that I hope this transfer doesn't happen. But I also believe, rationally, that it won't.