To those saying it's just the first season game, I get it. I think the worry for me is the pattern and style we saw before Arsenal towards the end of the season played out again with remarkable similarity.
By all means be slow, even a bit sloppy, but we were blasting long hopeful balls and bypassing the midfield again only to have it come straight back (looking at you Casemiro, but could be the instruction, as Bruno wasn't doing that at the Euros), there was the huge gap again, we always seemed outnumbered wherever we were on the pitch, Rashford and company giving the ball away in dangerous areas trying flicks that were not on and we were conceding chance after chance just like we did during last season, the almost identical sequences brought back the trauma!
In my years of watching United, I've seen us have many an underwhelming first game in pre-season, but to concede 22 shots? Surely that's a first. If Rosenborg were any good, they could easily have hit us for 8.