Not a problem and he was actually a lifesaver for his team.
I remember in the last season when Manchester United was not in a good situation and they totally lost the hope because of their place in the league, Ten Hag joined this team and he helped them to improve the team.
That's maybe a good reason to say a coach like Ten Hag needs more time in Manchester United.
Manchester United can beat Galatasaray, but it will be an away game, and they will also have a chance in the match with Bayern, since for Bayern this match will not decide anything, but even in this case Bayern will be a very strong team.
Erik Ten Hag's last season is enough backing, too much criticisms but it'll definitely take time before good and great things happen. He as a coach should know that he's been given too much time to turn things around. He's also been doing his best, it's just that some important players are absent and most of his plans can't work without these players.
Last season was a sexy one to an extent, Manchester United fans knew that, they didn't get enough high blood pressure like they've been getting this season. The Pre-season was clear that they'll be having a very tough season, it was difficult for some new players and old players in the club. It's said that they be suffering from the high intensity wanted by Erik Ten Hag and that broke players down. I do think that's the main issues with Jadon Sancho, taking lots of funds but can show working with his skills and pace on the pitch.
A team should never be underrated though, but Galatasaray should not be a threat to Manchester United if they had a good season from the Premier League. How well you play in the Premier League reflects on the Champions League games too.