“Fitness-wise he is close to the level he should be and we can judge him in a fair way from now on,” Slot told reporters on Friday.
“The first five or six weeks, of course we had the player we signed but he was not completely ready. He was getting fitter but he had to do this in a Premier League game.
“This is not normal for a player. Ideally you would use him earlier in friendly matches but there is no time in the middle of the season for a friendly so we had to build him up playing Premier League and Champions League games.
“You have to be on top of your game to make a difference at this level. You can play at this level if you are 80, 90 or 95 per cent, but to make a difference at the highest level of football you need to be 100 per cent.
“That goes for every player and I think I can safely say he is 100 per cent now.”
Asked what he wants to see from the Sweden international moving forward, Slot continued: “Goals. That is the most simple thing.
“But also to be the leader in pressing from our front three, there we can improve as well. That is something he needs to do but Hugo [Ekitike] the same.
“Of course if you are a No.9 at Liverpool you need to score goals but that is what he has always done in his life.
“The only thing he needs to be is fit and, if he is fit, our team is still creating the most chances from open play in the Premier League and we have the most shots on target in the Premier League from open play.”
