Rafa Benitez reacts to speculation over the Newcastle future of Aleksandar Mitrovic
Aleksandar Mitrovic's former club Anderlecht have been linked with a loan bid for the striker, who has only played 30 minutes of Premier League football so far this season.
However, United manager Benitez believes it's too early to think about January's transfer window.
"Every player who is not playing, the closer we get to January, there could be a rumour in the press," said Benitez.
"But, at the moment, we're working with 26 players in the squad to try to improve them. I cannot say 'I want to do this or that', because maybe we cannot.
"I had this conversation with an agent the other day, I said 'you have to wait until December to see where we are because if I say yes, he can go, after that we could have an injury'. So why do I have to sell my player if I don’t have a replacement?
"Then you go for the replacement and it’s £30million, or he wants to wait until next year, or won’t come because we don’t play Champions League.
"So why do I have to agree to something now when have two months to go? Are we working on names? Yes, you have to be ready."
Joselu has started eight out of Newcastle's 10 league games so far this season.