Ahead of tomorrow's trip to Newcastle, Slot was asked if Gakpo will hit 20 goals this season.
He said, "Unfortunately, I have experienced already that he is able to score 20 goals in a season when he played for PSV Eindhoven when I was at Feyenoord and he almost every time, scored against us. He was able to score in that league and almost definitely will be able to score that many goals here as well.
"Just like Mo, just like Lucho (Diaz), just like Diogo (Jota), just like Darwin (Nunez) as well. They are all capable of scoring that amount of goals.
"Now, unfortunately for them, they have so many good players around them that they don't start every single game, because that would help for them to get their numbers even higher, but if I combine the numbers of Cody and Lucho, they are probably coming close to the numbers Mo has, so it is the position that has to bring the numbers and the same for the nine position, as well as the right winger position.
"Cody is in a very good place at the moment, but I think you'll agree with me that Lucho is as well."
Asked about the pressure on Mohamed Salah to carry the attack, Slot also said: "Is it a danger putting too much on him? A bit, but only for the fact that he can, he's also a human being. It happened to him last season that he can get an injury as well and since Federico Chiesa has had a difficult start to the club because of injuries, we don't really have a replacement for Mo.
"The good thing is that Harvey Elliott is getting fitter and fitter again and he played this position many times as well. I'm not afraid that Mo's numbers will drop at all. When it comes to an injury of him, then we are in a better position on the left wing than we are on the right.
"The good thing is, Federico is also training with us. He is getting back and Harvey is getting back, but the best thing that can happen to us is that Mo stays fit and keeps producing these numbers."