Erik ten Hag was always likely to make changes given the packed fixture schedule, but few people expected as many as four for arguably the most important of the three matches before the Manchester derby.
Two of those came in defence where Aaron Wan-Bissaka rightfully kept his place, Luke Shaw was moved back to the left, and Harry Maguire and Victor Lindelof reunited in the middle.
Even against favourable opponents, it was always going to be a huge risk, but it certainly paid off. It ensured that a number of key players got valuable rest, others got eased back into action, and they still kept a clean sheet.
PLAYER RATINGS: How the United players rated vs Bournemouth
It only took one absence for United&aposs lack of attacking options to be exposed, with Antony&aposs injury heavily felt on the team sheet at least.
Anthony Elanga and Alejandro Garnacho were the only two forwards on the bench, neither of whom are strikers, and who have one league goal between them this season.
United&aposs need for a striker has been a talking point every week this season, even after matches they have won, but with the January window open, it is now even more relevant.
The big question is which kind of forward they require most. They are not only overly reliant on the misfiring Martial through the middle, but clearly lack a credible back-up option on both wings as well. There is an argument to sign two attackers this year.
It says a lot that although Ten Hag made changes, he didn&apost take any risks with his midfield selection. Casemiro kept his place at the base of the three, with Eriksen and Fernandes alongside him.
United&aposs midfield is the beating heart of the side under Ten Hag, not only in terms of the energy they bring to the pitch but also in the fact that they are the embodiment of the calm, composed approach he wants.
There is no better evidence of that than the opening goal of the game, as Casemiro met Eriksen&aposs superb free-kick with an even better finish.
Whenever they start, you sense United will win, though they&aposll have to find a way to do it without them across the next two matches in order to keep them fresh for the huge Man City clash.
A MESSAGE TO MAN CITY
Speaking of which, it might seem a way off yet, but United will already have one eye on that clash with City next week, their next match in the Premier League.
United have quietly gone about their business in recent weeks, while Pep Guardiola&aposs side have fluctuated from fantastic to frustrating with a number of disappointing results.
If they don&apost win at Chelsea on Thursday, then City would travel to Old Trafford with only two wins in their last five league outings and could even drop below United if they failed to win that.
Ten Hag will no doubt be urging the team to focus on the cup games that lie ahead, but it might soon switch to leapfrogging their noisy neighbours.
VAN DE BLEAK
You really have to feel sorry for Donny van de Beek. His performance wasn&apost perfect against Bournemouth, but it was most certainly an improvement on his recent ones.
The Dutchman linked up play well, even if his overall play remained rusty, and was gradually growing into the game as he matched his teammates&apos tempo.