Dundee United manager Craig Levein admits goalkeeper Grzegorz Szamotulski will leave Tannadice once his short-term deal expires.
The Pole has been hugely impressive since he was brought in as cover for injured countryman Lukasz Zaluska.
But Levein told the Scottish Sun: "I am now resigned to losing him in January when his contract ends.
"About two months ago we made him the best offer this club could make and he hasn't accepted it."
Celtic and Hearts have been linked with moves for the 31-year-old but Levein is in the dark about Szamotulski's next career move.
"When we signed him he did tell us that he would only stay until January and he hasn't changed his mind.
"We know we have done our best to keep him here and if a team the size of Celtic comes in for a player whose contract is about to expire, there is very little we can do."