United had to play a man light for 55 minutes at the raucous Wankdorf Stadion, where David Wagner’s Young Boys put in an impressive display and secured a famous 2-1 comeback win at the death.
“It’s in football in general, not just the Champions League, discipline is a huge part of the game,” Solskjaer said.
“Aaron’s normally a very, very astute tackler – one of the best in the world. We know we’ve given ourselves a more difficult task than what we did last year but everyone thought we were through after two games last year.
“You need 10, maybe 12, points, you need to win your home games, win one away from home.
“Of course we’ve lost the opportunity to get three points but we’ve got two home games next and got to focus on them two.
“The astroturf, of course, takes its toll as well and we wanted Nemanja (Matic)’s experience to keep hold of the ball and Jesse’s legs.”
As United nurse their wounds after a terrible start to Group F, Young Boys fans will be celebrating long into the night after former Huddersfield boss Wagner led them to victory.
“We’ve won a couple of games already, but to beat Manchester United in the Champions League is unique,” he said.
“I’m just really happy for everyone who witnessed it. Every single person here played their part. The lads went above and beyond their limits. That’s only possible with great support.
“We wanted to show our intensity, our aggression and our passion. The lads did brilliantly and deserve huge credit.”