Ekitike was forced off due to a knock in Liverpool's Champions League defeat at Galatasaray last night.
Slot said afterwards: "He felt something when he had to reach for the ball. I think we all know which one it was when we were trying to force something.
"I think at that moment in time, on the other side there was someone on the floor as well, so the referee blew his whistle and I wasn't even thinking we had an injury, but Hugo felt something.
"After the game, that's always the difficult thing with these moments when players feel like it is not too bad, but when you just walk around it is something different than when you make a sprint or have to shoot on target.
"He said he couldn't continue so we had to take him off. Let's see how he is for the weekend."
Alisson out of Chelsea trip
Meanwhile, goalkeeper Alisson was also forced to leave the pitch during the 1-0 defeat.
Slot said, "When he sprinted back he felt something. I cannot tell you (exactly) because I am not a physio, but normally when a player when he sprints back, feels something, goes to the floor and doesn't come back onto the pitch (it's not good).
"If my player is on the floor, I nine out of 10 times fear the worst – and by the worst I mean he cannot continue. That's what happened with Alisson.
"Normally, he will not be able to play Saturday. That's 99.9 per cent – I've already said 100 per cent, but let's make it 99.9 (although) I think it's 100."