Some might see the acquisition of the 23-year-old as another gamble, in an area of the squad when the Red Devils really can't take any more chances.
Youth over experience for United
Both Andre Onana and Altay Bayindir have shown, beyond doubt, that the goalkeeper's jersey at the Old Trafford outfit weighs far too heavily on them.
The only question United therefore needed to answer before the deadline, other than whether they would sign a new custodian in any event, is whether they would go for youth over experience or vice versa.
As it turned out, Lammens' youth and the good reports received on him saw Ruben Amorim turn away from a potential deal for Aston Villa's 34-year-old World Cup-winning keeper, Emi Martinez.
The Argentinian will likely feel justifiably unhappy that any potential move has collapsed, though it must be remembered that no official bid had actually ever been forthcoming from the north west giants.
Decent enough numbers from Emi Martinez
It's clear that Amorim needs a custodian that's good with his feet, and Martinez's 132 accurate sweeper keepings from 140 attempted during his time at Villa has often seen him register a perfect 100% record in this regard.
His save percentage has hovered around the low to mid 60 percent range and even went as high as 80% in last season's Champions League campaign, whilst his set-piece saving abilities have also remained at a consistent level and have actually improved in the time he's been at Villa Park - only 15.6% of free-kicks faced were successful in the 24/25 Premier League.
Martinez commands his area well, demands much of his defence and is an imposing presence when coming to gather crosses or narrowing the angle.
Only eight of the goals he's conceded in the past few seasons have been as a direct result of one of his mistakes, though six errors made leading to shots in 2024/25 were two more than the error-prone Onana posted.
10-year age gap a defining factor
Ultimately, a look into the future is what the Old Trafford outfit have banked on, and with Lammens having 10 years over his contemporary, despite a lack of experience, it's hard to argue with their decision.
The Belgian has certainly been winning the plaudits of late too.
"His shot stopping is his biggest quality," Belgian media recently reported. "He made some great saves and has great reflexes on the line.
"He is very proactive and likes to come for the ball. He has great feet and his passing is a really big weapon for any team looking to put some tempo into their play."
Comparisons with fellow Belgian, Thibaut Courtois, aren't therefore without foundation, and the Real Madrid stopper apparently told former Man United defender, Rio Ferdinand, that "Lammens is a huge talent, obviously not experienced yet, but his style is well-suited to the Premier League. He’s big as well.”
Lammens' lack of experience is stark
That lack of experience is stark, mind you, with just 56 senior appearances in the Belgian Jupiler Pro League and one in the Champions League to date.
His save percentage of 76.8% in the league last season is impressive, as is the fact that he's saved half of all the penalties he's faced (five from 10).
12 sweeper keepings from only 14 attempted has given him a high of 81.8%, though were he soon to establish himself as United's No.1, it's a fair bet that Amorim or any potential replacement will want to see a lot more tidying up from him at the back, followed by some quality distribution.
Just two errors made leading to goals and 11 clean sheets in those 56 appearances are other statistics that the youngster can be proud of, though the pressure is really on him to deliver at the highest level now.
One area that Lammens will need to improve upon almost immediately is when he wants to launch the ball upfield. In the 544 previous instances he's done so, only 148 have found their target.
A 71.6% pass completion in the league last season is reasonable enough though not fantastic, but it does represent an improvement on previous campaigns where he posted figures of just 65.4% and 40.4%.
Back to the drawing board if Lammens can't settle quickly
Lammens certainly has time on his side in terms of his age though perhaps not so much with regards to how quickly he needs to settle into the squad and go about producing his best work.
If he can fulfil his early promise, then Man Utd will have landed themselves an £18.1m bargain. If not, it's back to the drawing board for the Red Devils hierarchy.
