Klopp revealed that the striker was frustrated for squandering so many chances but hailed his contribution as "insane" and "impossible to defend".
"An insane first half, unbelievable, I would say not to defend. Outstanding, really good," he said.
"Why do we speak about Darwin? Obviously because he has so many situations where he missed but it was the first game since we count that a player hit the woodwork four times in a game. Now think you are in his boots, how that feels. Missing a penalty, you could see it at half-time, he was really upset with himself.
"It is just crazy that he creates that many. Imagine for a second he would take them all... the numbers would be absolutely insane to the extent where you wouldn’t understand it anymore, so it’s normal. For us it is important because we scored four goals, who cares if we could have scored a fifth or a sixth? It is really not important. We need to win football games – and he will score. He scored already. Then setting up in a really important moment the fourth goal, because 3-2 or 4-1 is a big difference, that makes him really the player he is for us. The rest will come, definitely."