Crystal Palace boss Oliver Glasner confirmed that 20-year-old Matheus Franca will be unavailable for "the next weeks" after suffering a rib fracture in training.
The Brazilian, who joined the South London club from Flamengo, has made just two starts for the Eagles since arriving last summer.
Commenting on the players at his disposal for Sunday's opener against Brentford, Glasner said: "It looks pretty good. All players are fit. Franca fractured his ribs and is out for the next weeks."
Joining the club for a fee that could rise to £26 million, Franca has endured an injury-stricken spell at Selhurst Park - struggling with a groin problem for the majority of last season.
Franca had just made a full return to training but now faces another setback, which could take up to six weeks to heal.
Other than the 20-year-old's absence, Glasner has a complete squad to pick from for the trip to West London.
Marc Guehi has been subject to four bids from league rivals Newcastle, but the Palace boss noted that the England international has trained all week and is in line to start at the Gtech Community Stadium.
Glasner said: "He trained today with us. We talked. I have no other information. I need to check my bank account to see if anything came in, but it doesn't look like it. He's our captain and I can't say anything else.
"Everyone trained. I'm very close to all the players. As long as nobody tells me gaffer I will leave, or the club tells me this player will leave, we will work with them everyday to ensure we are ready and competitive for a Premier League game.
Crystal Palace have made three additions in the summer transfer window. Brimming with confidence, Glasner shared his content with his squad.
"At the moment, everyone is available for Brentford. I'm very happy with the squad. This week was the first week we had the whole group together, but we have a great mood on the pitch and in the dressing room. I'm very confident we are ready for Brentford."
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