Julian Nagelsmann says Bundesliga leaders RB Leipzig must learn from their humbling at Manchester United as a Marcus Rushford hat-trick poured cold water on the German side's Champions League aspirations.
Rushford scored three second-half goals at Old Trafford on Wednesday to seal a 5-0 rout of Nagelsmann's Leipzig in Group H.
The German league leaders host Paris Saint Germain next Wednesday in a repeat of last season's Champions League semi-final, which the Germans lost 3-0 in Lisbon, and Nagelsmann demands they heed their Old Trafford lesson.
"We were sent packing, but it's not a drama - it's happened to other teams before," Nagelsmann insisted after the match.
"We've learnt a bit of a lesson and can play much better.
"We only have ourselves to blame for the size of the defeat, which could have been avoided."
Nagelsmann says his players were found wanting physically against a robust United team.
"The physicality of Man U is quite impressive, we have ground to make up," he admitted.
"Just the sheer size of the opponents, who were superior to us in the air, but also on the ground.
"The Premier League is obviously tougher than the Bundesliga when it comes to challenges - we had to get used to that."
Leipzig were only 1-0 down at half time due to a goal by United's 19-year-old striker Mason Greenwood.
However, England forward Rushford came off the bench in the second-half and ripped through the German defence with three goals in just under 20 minutes while Anthony Martial also scored.
"We could have defended the first goal. After that, we didn't do so badly, were still in the game and won a lot of ball," said Nagelsmann.
"Then we went 2-0 behind and the way we played in the 15 minutes after that were the worst in a long time."
Nagelsmann, 33, is one of the rising star coaches of German football, but is notorious for having a bad mood after defeat.
"I'm a football coach, not a model," he tersely replied when a reporter ask about the eye-catching chequered jacket he wore on the sidelines.
He has been tipped as a potential future coach of both United and arch rivals Manchester City.
"Today is completely the wrong time to comment - it's relatively normal that names are circulated and traded in football," he said.
"What counts in the coming weeks is the success of my team, the work with my players, the success of RB Leipzig.
"That is what I am focused on."