Napoli will reportedly demand a fee of €100million (£88m) for highly-rated defender Kalidou Koulibaly.
The Senegal international is a target for several Premier League clubs including Manchester United and Arsenal.
But his Serie A club – who finished second behind Juventus in Serie A this season – have issued a hands-off warning.
According to the radio station Radio Kiss Kiss Napoli, the club’s director of sport Cristiano Giuntoli will only consider a huge offer.
Should the defender be prised from Naples, the fee would represent an incredible profit on the €7.75m Napoli spent to sign him from KRC Genk four years ago.
Transfer gossip from Wednesday’s Daily Mirror
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Arsenal have held talks with Nice midfielder Jean-Michael Seri – but are set to be beaten to his signature by Chelsea.
Harry Maguire future is set to be decided after the World Cup with several top clubs eyeing the Leicester defender .
Jonny Evans has played his last game for relegated West Brom and is holding out for a switch to champions Manchester City.