Swansea City director John van Zweden says four Premier League clubs have made inquires regarding goalkeeper Michel Vorm.
The Dutch stopper has made quite as impact in his first six months in English football, claiming nine clean sheets in 21 league appearances for The Swans.
Vorm has also built a reputation of being tough to beat from the penalty spot, saving from Wigan Athletic's Ben Watson and Fulham's Clint Dempsey, exploits that have attracted interest from the Premier League's elite.
"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."
Of the quartet who have enquired into Vorm's availability, Spurs are the side with the greatest need, with Brad Friedel likely to retire following the expiry of his contract at White Hart Lane, which runs until 2013, while Carlo Cudicini has only featured in the Europa League this term.
Heurelho Gomes has fallen out of favour with Harry Redknapp, having featured just four times in the current campaign and is likely to leave next summer, if not before.
Manchester United have signed two goalkeepers in the past 14 months in the form of Dane Anders Lindegaard, and Spaniard David De Gea, both of whom have been rotated this season.
Despite Petr Cech's previous injury problems, the 29-year-old isn't expected to be replaced at Stamford Bridge any time soon, while in reserve Thibaut Courtois has made seven clean sheets during his loan spell with Athletic Madrid.
Newcastle United may only be forced into moving for Vorm if they lose their currently stopper Tim Krul, who has been linked with a move to Tottenham in recent weeks.