Chelsea's scouts remain hard at work in search for a long-term answer to their goalkeeping issues, 90min understands.
The Blues wanted a new stopper heading into this summer and, after Edouard Mendy was sold to Al Ahli, a £25m deal was struck to sign Robert Sanchez to offer competition for Kepa Arrizabalaga, who was later loaned to Real Madrid in the hope of securing a permanent exit next summer.
Kepa's departure triggered a £14m move for 23-year-old Petrovic, who has been the back-up to Sanchez during Chelsea's underwhelming start to the campaign.
While Chelsea are satisfied with both Sanchez and Petrovic, 90min understands the Blues remain on the hunt for a new long-term goalkeeper to add to Mauricio Pochettino's expensive squad.
Interest remains in Porto stopper Diogo Costa, while 22-year-old Valencia goalkeeper Giorgi Mamardashvili is understood to be close to the top of Chelsea's wish list.
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Closer to home, Chelsea are among the teams tracking Everton's Jordan Pickford. England's starting goalkeeper signed a new four-year deal in February but the Toffees' well-known financial issues, coupled with their struggles towards the bottom of the Premier League, may see a deal become possible in the future.
Sources have confirmed to 90min that a January transfer is unlikely, with club officials currently happy to see out the season with Sanchez and Petrovic before evaluating their options at the end of the campaign.
Next summer will see Kepa's loan to Madrid come to an end. There is no purchase clause in the deal and no guarantees the Spanish side, who expect to have Thibaut Courtois back from injury, will pursue a permanent transfer.
Also returning from loan will be 19-year-old United States international Gabriel Slonina. A £12m signing from Chicago Fire, Slonina joined Belgian side KAS Eupen this summer for his first taste of European football.