United endured a bitterly disappointing start to the season, losing two of their first three Premier League matches for the first time since 1992/93, but back-to-back wins against Burnley and Watford respectively have helped to steady the ship.
Mourinho's men are chalked up as 7/10 (1.70) favourites with bet365 to open their Champions League campaign with victory on Swiss soil.
Luke Shaw was not in the squad Watford on Saturday after suffering concussion on international duty earlier this month and the full-back may well miss out again in Switzerland, although he has at least travelled.
Guillaume Hoarua scored twice in the previous round of this competition to send Young Boys into the group stages at the expense of Dinamo Zagreb and, with six goals in his last eight matches, he is a man in form.
Visitors to get amongst the goals?
Manchester United have scored twice in four of their five fixtures this season and, with Romelu Lukaku in sparkling form, they will be confident of making their mark in Bern.
That latter play would have landed in three of the last four matches that Mourinho's men have contested.
There have been 13 goals scored in Young Boys' four competitive matches on home soil so far this season, but a 4-0 hammering against Wolves in pre-season is, perhaps, indicative of the gulf between the sides.
As such, bet365's 8/5 (2.60) quote for Manchester United to win a match in which at least three goals are scored could represent real value for punters ahead of Wednesday's clash.
Odds correct at time of writing. Please gamble responsibly.