Eliaquim Mangala
Porto yet to receive an offer for Mangala. (Reuters)

Porto president Pinto da Costa has insisted the club are yet to receive any proposals for the club's in demand trio of Jackson Martinez, Eliaquim Mangala and Nicolas Otamendi after the latter two became reported targets of Manchester United and Chelsea.

France international Mangala has been persistently linked with the Premier League duo since the summer transfer window with both clubs reportedly keen to add the powerful centre half to their respective defences.

Similarly, Argentine defender Otamendi was subject to reports in the Spanish media suggesting he has already agreed a deal in principle to join Chelsea ahead of the 2014/15 season after the Blues reportedly fended off interest from Barcelona and AC Milan for the 25-year-old's signature.

But while the centre half paring remain linked with moves away from the Estadio El Dragao, Da Costa appears untroubled by growing speculation surrounding the futures of his star players.

"Every day it is said in the newspapers that this or that club wants Mangala, but Porto did not get any proposals," was quoted as saying by Tutto Mercato Web.

"Jackson's (Martinez) name also appears throughout the press, but no one contracted us.

"And finally, Otamendi's name is also put out everywhere, but no club has ever asked us for him."

Reports have also suggested United are willing to offer Brazilian midfielder Anderson to Porto in an attempt to convince the Portuguese champions into listening to offers for Mangala. Such a move could see Chelsea left to pursue Porto's other defensive option Otamendi, who has a release clause of €30m.

While interest from the Premier League in Martinez has faded since the summer the striker had been heavily linked with a move to Liverpool, but it would now appear Napoli are the favourites to sign the Colombia international.

While Martinez remains contracted to the Portuguese champions until the summer of 2017, the futures of defenders Mangala and Otamendi, who are contracted to Porto until 2016 and 2015 respectively, remains less certain.