The Red Devils got their Champions League campaign off to a dreadful start as they lost 2-1 in Switzerland.
Cristiano Ronaldo gave Man United the lead but Moumi Ngamaleu and Theoson Siebatchu's stoppage-time strike saw the three-time European champions leave empty-handed.
Man United had their setbacks with Aaron Wan-Bissaka perhaps unfortunate to receive a straight red card in the first half, while it's difficult to legislate for Jesse Lingard's dreadful backpass which directly led to the winning goal.
But the performance as a whole 'exposed' their manager's shortcomings once again, says Cundy, who believes it's time for the club to get rid of Solskjaer and get in former Chelsea boss Antonio Conte.
"That there shows he's utterly clueless," Cundy said on the Sports Bar.
"That performance, the team shape… they went down to ten men, yes, but come on. They went to five at the back and he didn't change it.
"They were getting overrun in the middle of the park. Poor Fred, Paul Pogba and Bruno Fernandes. I've got so much sympathy for them, they had no help, they were getting passed around.
"The back five didn't move, they were getting outnumbered. It wasn't working, they should have gone for four in defence and four in midfield.
"United got exactly what they deserved and he's been exposed again brutally.
"The game changed on the red card but that didn't mean it was over.
"Young Boys are normally whipping boys of European football and United get rolled over 2-1… it was a disasterclass, it was an absolute disaster.
"It exposed Ole, it did badly. I'd sack him. We know what's coming, don't we? You've got Antonio Conte out there…
"Who's the better manager? There will be a stage in the season where they'll be like 'I wish we did it earlier.'
"There's been a pattern emerging with Ole, particularly in Europe. He couldn't get out of the group last season.
"It did him a favour going into the Europa League, it's an easier competition to win and he managed to balls that up."
Cundy's claims where echoed by Danny Mills, who lambasted Man United for 'inviting pressure' on themselves.
"To sit back and just invite pressure on, I think it was about 70 per cent possession for Young Boys in the second half," Mills said on talkSPORT 2 as the final whistle went.
"It's Young Boys. It's not Barcelona, or Chelsea, or Manchester City you're playing against.
"I know they had ten men but they should be better than that."
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