Unfortunately, Zlatan will do very well IMO. He is an extremely strong player and will have pacy players running off him in exactly the style that Mourinho prefers. I hate to say it but I maintain that they will be genuine contenders this season, Pogba or no Pogba.
Longer term, they may be able to buy their way from trouble but the lack of investment in infrastructure is really what sets us apart from them in terms maintaining the success. Mourinho does not provide a long term platform either so hopefully they will suffer a torturous and expensive decline.