Liverpool manager Jurgen Klopp praised Loris Karius and feels he would be proven an "idiot" if the goalkeeper was not a good shot-stopper.
Karius kept a clean sheet as Klopp's side recorded a 2-0 win over Newcastle United in the Premier League on Saturday.
The German goalkeeper has become first choice at Anfield, having arrived from Mainz in 2016.
Klopp said he had been pleased with the progress the 24-year-old Karius has made since joining the club.
"Look, if he was not a good goalkeeper I would be the biggest idiot in world football if I line him up. Maybe a few people think I am, but he is an outstandingly skilled goalkeeper," he told a news conference.
"The start was not very good and in our life people make their assessment immediately and say the start was bad so there's nothing.
"He needed time and needed the situation, he needed the training with John [Achterberg, goalkeeper coach] and now he is playing. Thank God, he is playing well. That's the situation.
"There is no goalkeeper without any mistakes in the world. For goalkeepers, the timing is very important.
"The best thing is that you don't make a mistake in the first 50 games; then people think you are the best and you can be responsible for three goals in a row but people still think 'but he is world-class'.
"He has had a few good games - that's good for us. Let's carry on."