Manchester united having Eric Ten Hag is a great achievement for the club, he had really helped the club in improving the performance of the team. With Eric Ten Hag Manchester United will achieve better position in every competition even if they are unable to win trophies. Barcelona match against Manchester United will be interesting and tough, it is not going to be a threat in any form . Manchester United is good enough to challenge any strong team without having any fear.
The only problem is MU has a very bad head to head against Barcelona. which will become a challenge for MU. MU must have won against Barcelona or it will be kicked from europa league. Ten hag may be able to make MU to go up again after MU has very bad result during the early season in EPL but this is a bit different caused by MU will be facing a team that was so difficult to be beaten by MU since a long time ago. I meant Barcelona was able to win against MU so many times with a different coach.
This gonna be a big challenge for sure. I hope that MU will able to win in the first leg against Barcelona.
The head to head record really can't be a problem and can't be used as a benchmark for how the team is performing at different moments, because there will be times when they get different results from the head to head record you are concerned about. Because after all, Manchester United still has a chance to beat Barcelona in this round.
Also, even if for example Manchester United still can't beat Barcelona, but Erik ten Hag will certainly be able to give Manchester United a good position or in the top four at the end of the season. That way, next season Manchester United will play again in the Champions League and that will still be good for Erik ten Hag's achievements as well because Manchester United will no longer only play in the European League.