Mourinho went on suggest he "did not know" when Paul Pogba would return from his hamstring injury, while Marcus Rashford is fit to play against Huddersfield on Saturday after an injury scare in Wednesday night's Champions League game against Benfica.
The return of the illustrious Swede who will wear the club's No. 10 Jersey will be a welcome relief to Romelu Lukaku who might otherwise find himself under pressure owing to the sheer number of competitions the Mancunian side will have to battle it out in during the festive period.
However, he'd sustain a serious knee injury, United made a decision to pass up on offering him a new deal, but that has since changed.
"Zlatan is here. He's working here and under our control", said Mourinho.More news: State unemployment rate remains stable
"He did it (recovery) very well, I talked to Zlatan while at the gym a while ago, I think he hopes to get back in December or January", Cole told FourFourTwo. Let him take his time and be back when everyone feels is the right moment.
"Paul is not here, I don't know when he comes back", Mourinho added.
"Yes is true I wanted four players and I think clearly everybody knows the position, maybe you know the player, didn't happen but we adapt to it and try the best we can. Yes I do, but it's just a feeling".
But it wasn't the ideal transfer window, with Mourinho voicing his desire to secure an attacking wide player - namely Ivan Perisic - before the window closed, but no such deal ever materialised.
On United's general injury situation, he said: "The injury process normally is a process of some guys get injured, some guys recover from injury, unless we lose completely the balance, this happens to nearly every team. And yes in answer to your question, nobody is back from injury but what we have is good".