Porto maintain the €15m release clause for manager Andre Villas-Boas has not yet been triggered, as their coach looked set to head to Chelsea.
The Blues are seeking to replace Carlo Ancelotti, who was unceremoniously axed at the end of last season, just 12 months after guiding the west London club to an historic double.
With Guus Hiddink - who enjoyed a successful spell as caretaker at Stamford Bridge in 2008/2009 - now appearing set for a sporting director role once a £4million compensation agreement from his departure as Turkey national team boss is secured, Chelsea seem ready to bring in a younger coach to oversee the first team.
Villas-Boas, 33, would certainly be no stranger to Stamford Bridge, having worked there under Jose Mourinho, and the Portuguese coach has seen his stock rise after guiding the Dragons to domestic and Europa League success last season.
However, the Dragons insist as yet no deal has been done for his departure.
"So far this club has not received any communication that this clause has been exercised, nor of the agreement of the coach that is desired," a Porto statement read.
Despite their determination to keep hold of Villas-Boas, president Pinto da Costa admitted the club could not prevent their manager from leaving should certain financial conditions be met.
"Villas-Boas has a contract and a clause of 15million euros," he confirmed.
"If someone deposits 15million euros into our account and he wants to go, we can not do anything because it is something that is contractually specified."
While there has as yet been no official comment from Chelsea, reports suggest a £4.4m-a-year salary is on the table for Villas-Boas, who could bring star striker Falcao to Stamford Bridge along with him.