Liverpool were knocked out of the Carabao Cup against Arsenal on Thursday
The Reds were beaten 5-4 on penalties by the Gunners at Anfield in their fourth round tie after dominating a goalless 90 minutes.
Klopp made nine changes from the Premier League meeting between the sides on Monday.
Teenage duo Rhys Williams [ making his Anfield debut at centre-back ] and Neco Williams both started, while Harry Wilson made his full Reds bow despite ongoing interest from Burnley.
Klopp was impressed by the youngsters, despite Wilson missing the decisive spot kick in the shoot-out.
"Rhys Williams did exceptionally well, Neco had one or two (difficult) moments but had a really good game, don't forget he played against Nicolas Pepe,” said the Reds boss.
"Harry Wilson, my God, he played in centre-mid and defended well. I like a lot of parts of the game but we lost in the end and that's the part I don't like.
"It is not too easy in a squad like this but they learn and want to learn and they are able to perform in a tricky game today.
"It was tricky not only because they were young but because their manager sends them on to the pitch in a team which doesn't usually play together."
On his side's defeat Klopp added: "Yes, we could have been a bit more clinical in finishing but Leno made a really good game.
"In the end the penalty shoot-out, it is luck and a lot of things, but Arsenal shot really well and us not exactly the same and that is why we lost."