Chelsea and Atletico Madrid announced on Thursday that they had reached an initial agreement that would see Diego Costa return to the La Liga club.
“Atletico de Madrid and Chelsea have reached an initial agreement for the transfer of Diego Costa,” the Spanish side said in a statement.
“The agreement is pending the formalisation of the contract between our club and the Spanish international forward.
“The English club has authorised Diego Costa to travel to Madrid in the coming days to undergo medical tests and settle his contract with our club.”
Chelsea said they had “agreed terms with Atletico Madrid for the transfer of Diego Costa”.
“The transfer will be subject to the agreement of personal terms and a medical.”
Costa, 28, has been frozen out by Chelsea manager Antonio Conte and spent the transfer window angling for a return to former club Atletico that never materialised.
Both Marca and Mundo Deportivo newspapers earlier said the two clubs had sealed a deal for the Brazil-born forward’s return to Spain until 2021.
The deal was worth 60 million euros ($71.3m), according to AS, while Marca said Atletico will pay 55m euros with a further 10m euros in add-ons.
Costa will not, however, find himself straight back in action, with Atletico officially banned from signing new players until January.
Costa was not included in Chelsea’s 25-man squad for the Champions League group phase, ironically drawn in Group C along with Atletico.
That ensured he would not become cup-tied and therefore remains free to play in the competition for another team in the second part of the season.