The Spaniard only joined the Serie A outfit in 2013 for a fee of around €9 million, and he has certainly proved to be good value for money by finding the back of the net 15 times in 37 league appearances during his first season in Italy.
His performances appear to have caught the eye of both Chelsea and Manchester City, but Corriere dello Sport say that if either club want to lure him from Naples it is going to cost them more than three times what Rafa Benitez paid for the striker 12 months ago.
Plus another obstacle that both could face is that Napoli are not willing to sell. Club President Aurelio de Laurentiis has a reputation as a tough negotiator and won't make life easy for either Chelsea or Manchester City should they make a move.
Just this weekend De Laurentiis told Arsenal they would have to cough up €56 million if they wanted to sign talented youngster Lorenzo Insigne, and the two Premier League giants can expect much the same treatment.
Chelsea are expected to have a busy summer with a host of new faces believed to be on the verge of arriving at Stamford Bridge. Diego Costa is said to have completed a medical, while deals for Filipe Luis, Cesc Fabregas and Tiago could also be done soon.
Manchester City meanwhile appear somewhat less interested in getting their business done before the World Cup, wile the fact that they can only spend €49 million on new players this summer as part of their Financial Fair Play punishment means they will have to choose their targets carefully.