Wilfried Zaha is starting a programme of rehabilitation from injury, according to Crystal Palace manager Frank de Boer, who does not know how long the winger will be sidelined for.
Zaha injured his knee during Palace's opening round defeat to Huddersfield Town, and De Boer has been without the 24-year-old for his side's subsequent loss to Liverpool in the Premier League, followed by an EFL Cup victory over Ipswich Town.
The Ivory Coast international scored seven league goals for Palace in 2016-17 but De Boer would not say if he will recover in time for the visit of Swansea City to Selhurst Park on Saturday.
The Dutchman told Sky Sports: "Wilf is a very robust player, the first couple of days [after the injury] are very important to have a rest and, from now on, I think he's going to start rehab.
"We don't know how long it will take.
"The risk is that you start too early, that he can have a setback, so we are going to see and won't put a time on it right now."
De Boer utilised fringe players Sullay Kaikai and Jason Eyenga-Lokilo against Ipswich and he praised their performance.
"Some players are coming back from injury, some players are waiting for their chance," he said. "I said to them before the match you have to show yourself and make it as hard for me as possible, so that if I need you I don't have to hesitate and I think a lot showed they are ready."
Asked if the club had made progress on any transfer targets, De Boer said: "I already said we are looking very hard and if something happens you'll be the first to hear it."