Liverpool defender Trent Alexander-Arnold is a doubt for Sunday’s final against Newcastle at Wembley.
The England defender was substituted in the second half against PSG after appearing to jar a knee in a challenge with Vitinha.
“He had to come off – that’s never a good sign,” said Arne Slot.
“From what I heard from people that saw the images of how he got injured, it didn’t look very good.
“I would be surprised if he is [available] for Sunday.”
Alexander-Arnold missed last year’s EFL Cup final win over Chelsea.
England manager Thomas Tuchel will name his first squad on Friday for World Cup qualifiers against Latvia and Albania this month.
Alexander-Arnold, who has 33 caps, was expected to be included.
