Swansea director John van Zweden has claimed Manchester United and Chelsea have made enquiries about goakeeper Michel Vorm.
Dutch keeper Vorm has been one of the stars of the Premier League season, with his consistent excellence winning him many admirers.
Swansea paid just £1 million for his services from Dutch side Utrecht and could well cash-in for a sizeable profit.
Losing Vorm would represent a major blow for Swans boss Bredan Rodgers but with the club thought to be willing to accept a decent offer, the big boys appear to be circling.
"Clubs have enquired about Vorm," Van Zweden 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."
Manchester United shelled out a fee in the region of £18 million for David De Gea last summer, but he has not convinced and it would appear the reigning Premier League champions are considering other options - while Chelsea may well be planning for life after Petr Cech.
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