It is an embarrassing result for Ten Hag and his team for allowing themselves to be trashed by Flamengo U20 team, this is a youth team we are talking about. It might not be an important game but Such results are not good for the team morale especially before the season kicks off. It is obvious they need to improve and do better next season, Ten Hag also needs to prove Manchester United wrong for sacking him by getting good results next season.
I actually do not see it as embarrassing enough, I even feel it has some intentionality in it, maybe they used that to get the team ready for the season and they actually did not take that game serious enough to want to win, in as much as I will not want to judge this game, I still think Ten Hag has to improve with his tactics and his technicalities so that by the actual season he will be able to get the team in their best form and get team in their best form to be able to deliver the kind of results and possibly win trophies as expected of them.
Erik Ten Hag will be the most watched manager in the Bundesliga this year, as everyone knows he was a failure at Manchester United. Leverkusen appointed him after a fantastic manager and faced a lot of criticism for this decision. There were those in Germany who argued that he needed a better manager. This criticism intensified after their devastating defeat against Flamengo's youth team. Now, Bayer Leverkusen enters the Bundesliga with a significant question mark. I hope things go their way.