Because Ten Hag had a very difficult season at Man United, it was felt that he was considered a bad coach. And especially as Xabi's replacement, it would certainly be considered very bad if he couldn't deliver the best results.
Unfortunately, in this opening match, Ten Hag was actually embarrassed by being defeated by Flamengo U20, even though it was a friendly match.
Source: Full-time in Rio 90+4' | 5-1
I'm sick and tired of watching elite teams losing heavily in the preseason friendlies. I don't take these games too serious. Erik Ten Hag is not showing any slide opportunity of succeeding with Bayer Leverkusen. Alot have happen over the past few weeks since he was appointed as headcoach for Leverkusen, watching them crumbled in the friendlies is definitely not a good review. Well we can all see it as a friendly game but that wouldn't be a good start or approach when Bundesliga reopen and seeing such defeats coming on the records for Leverkusen. None of us would like to entertain or accepts defeats, perhaps we can keep our spirit high when our favorite club have signed prominent players. Unfortunately, in this opening match, Ten Hag was actually embarrassed by being defeated by Flamengo U20, even though it was a friendly match.
Source: Full-time in Rio 90+4' | 5-1