Jadon Sancho has struggled to settle at Manchester United. Photo: AFP
Sancho, who cost United £73 million ($92 million) when he moved from Borussia Dortmund in 2021, has been in exile since he was cast aside by Ten Hag in September.
The England international was told to train on his own after posting on social media that he had been made a "scapegoat" by his manager.
A January move would appear to suit all parties, but United would face having to take a massive loss on any transfer fee and potentially subsidise Sancho's reported £350,000-a-week wages.
However, Ten Hag said the door is still open to the 23-year-old if he is willing to toe the line set by the former Ajax boss.
"It is about a culture and every player has to match certain standards and it was about that," said Ten Hag.
"What will happen there? He knows what he has to do. If he wants to return, it is up to him."
Sancho has scored 12 goals in 82 appearances for United but his absence has opened the door for Alejandro Garnacho to feature more regularly in recent months.
Garnacho was selected ahead of Marcus Rashford for Wednesday's 2-1 win over Chelsea and set up the winning goal for Scott McTominay.
"There is big potential and there is a lot to build on but we are happy with his performing in this moment and happy with his contribution," Ten Hag added.
"The foundation and basis is always the defending part of his game but attacking-wise he has the key actions - assists, counter-attacks and scoring goals, that is very important for an offensive player that you have the production."
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