Swasea director John van Zweden has revealed that Chelsea and Manchester United have enquired about goalkeeper Michel Vorm.
Vorm joined Swansea in the summer frm Dutch outfit FC Utrecht and has established himself as one of the top shot-stoppers in the Premier League, with nine clean sheets in the league to date.
The 28-year-old's form has not gone unnoticed, and Van Zweden has revealed that four Premier League clubs - Chelsea, United, Spurs and Newcastle - have made tentative enquiries regarding the Dutch international.
"Clubs have enquired about Vorm," he told VI Radio.
"Manchester United have asked, in addition Chelsea and for that matter Newcastle United. Tottenham Hotspur have cautiously announced they are interested.
"It would be a nightmare for us if he left."
Swansea signed Vorm for a fee in the region of £1.5million in the summer but can expect a significant profit if they are forced to cash in on the keeper.
However, a January move seems unlikely as Vorm is eager to establish himself as the Netherlands' number one ahead of Euro 2012 and the Dutchman will be keen to remain at the Liberty Stadium as first-choice rather than fight for a starting spot elsewhere.