Liverpool manager Liverpool said he will not judge the performance of his inexperienced side as a young Reds team suffered a 2-1 Europa League dead-rubber defeat to Union Saint-Gilloise in Brussels.
Klopp made a number of changes with his team already safe as Group E winners and with an eye on the weekend's Premier League game against Manchester United, starting six players aged 20 or younger.
Klopp's team was the youngest in their history by some margin to play a European game with an average age of just 21.9 years. And it showed against the Belgian league leaders.
Saint-Gilloise, who needed a victory to keep alive their hopes of pipping Toulouse to second place, took the lead through Mohamed Amoura before Jarell Quansah hit back for Liverpool.
Cameron Puertas restored the hosts' advantage two minutes before half-time with a low strike which beat Caoimhin Kelleher at his near post.
Klopp put in Joe Gomez, Ryan Gravenberch and Darwin Nunez in the second half, but Saint-Gilloise held on for a famous win, although the Belgians dropped into the Europa Conference League play-off round after Toulouse beat LASK Linz 2-1 in the group's other game to finish second.
Klopp took responsibility for the result.
"I mixed up the team completely, so I think the changes we made, the amount of changes, were too much for rhythm," he said.
"I would never judge a player after a game like this and say, 'OK, he's obviously not good enough' or whatever. I know how good they are because I see them every day in training and tonight is an important experience.
"I don't think any career ever started without these kind of games where you have to struggle, where you have to fight through, where you have to survive.
"For some it was a really important experience and for others good for rhythm. I saw good performances.
"Of course as a team it is not a fair assessment if I say now they are top of the table in Belgium and we come here, bring kids - altogether that's really difficult - but I thought we gave it a go and that's OK for me.
"Nobody got hurt, nobody is injured, so we recover, go home and go again."
