Position last season: 6th
Player arrivals: Victor Lindelof (£31million from Benfica), Romelu Lukaku (£75million from Everton), Nemanja Matic (£40million from Chelsea)
Player departures: Josh Harrop (Free, Preston North End), Zlatan Ibrahimovic (Released), Sam Johnstone (Loan, Aston Villa), Adnan Januzaj (£9.8million, Real Sociedad), Dean Henderson (Loan, Shrewsbury), Wayne Rooney (Free, Everton), Regan Poole (Loan, Northampton), Cameron Borthwick-Jackson (Loan, Leeds)
Jose Mourinho lifted three fingers in Stockholm and his playing staff did likewise.
Three fingers, symbolising the three pieces of silverware United had landed during his debut season at Old Trafford: The Community Shield, League Cup and Europa League.
However, perhaps the more pertinent number for United supporters was 24; the number of points the sixth-place Red Devils finished behind Premier League winners Chelsea.
For while getting back into the Champions League through the back door ensured the campaign ended with United back where they belong in terms of European football, domestically, they remained some way off the pace.
United lost only five times in the league last term, but won only 47 per cent of their fixtures.
They drew 15 times - Chelsea, who also lost five times, drew only three of their matches, Arsenal, who lost nine times, drew six - and goalscoring was their Achilles heel.
United scored a meagre 54 times last term, some 31 less than the champions, 23 less than Arsenal in fifth and even one less than ninth place Bournemouth. Zlatan Ibrahimovic struck 17 times, but no other United player managed double figures; Juan Mata was second top scorer, with six.
Now Ibrahimovic has departed, likewise Wayne Rooney who has headed back to Everton. Instead, Mourinho has turned to Romelu Lukaku, a player he allowed to leave when in charge of Stamford Bridge, but who has flourished and matured during three years at Everton.
The Belgian scored 25 league goals during 2016-17 and now offers United a threat in behind, while also retaining the physical presence of Ibrahimovic.
Often during his time in England Lukaku has been cited as a player who doesn't score against the so-called 'big' sides. But it's his reliability in putting the supposed lesser lights to the sword that is what United need, as they seek to rectify a situation that saw them drop 23 points at home last term.
Equally, United's other attacking options need to do more. Paul Scholes was frank about it after the Super Cup defeat to Real Madrid. Henrikh Mkhitaryan, Jesse Lingard, Anthony Martial and Paul Pogba all must "step up this year" according to the club legend, and he's right - if United are to challenge for the title, they need to be aiming for 10 goals-plus each. Marcus Rashford also must become more reliable in front of goal, while Mourinho still wants to add more threat from wide areas.
Pogba has become an increasingly influential figure in the dressing room, the Frenchman having emerged as a leader since his record signing from Juventus 12 months ago.
The 24-year-old gradually grew into his role within the side last term, and now the arrival of Nemanja Matic from Chelsea should enable Pogba more freedom.
Matic remains an excellent midfielder, bringing control and aggression to midfield; in big games, expect United to go with the formula they showed in the Super Cup, with Matic sitting, Ander Herrera tight on his side, and Pogba offering more verticality to the left, going both ways. Often last season Pogba played either as a No.6 in a 4-2-3-1 or in the No.10 position, but it is in a 4-3-3, as a No.8, playing on the half term, working both ways and carrying the ball, where he thrives.
In attack Mourinho has a plethora of options, but it is in defence where the Portuguese remains unsure, and £31million Victor Lindelof has only added to that uncertainty after his arrival from Benfica.
The Swede had been chased for 12 months by United officials, but he has struggled in pre-season and there are big question marks right now over whether the United shirt is too big for him; only time will tell.
Eric Bailly is likely to be the No.1 centre-half, having widely impressed last term, but Mourinho is yet to commit to a centre-back partnership. Likewise, the situation at left-back is just as complicated, with Matteo Darmian, Daley Blind - also a central defensive option - and Luke Shaw all options. The only position it appears Mourinho is certain on is at right-back, where Antonio Valencia continues.
In goal, David de Gea remaining once again is an unquestionable plus. The Spaniard is now firmly established as the Premier League's No.1, and Sergio Romero remains a more than capable deputy, happy to play second fiddle.
Mourinho sides throughout his managerial career have always peaked in his second season. At Porto that meant winning the Champions League, likewise at Inter. Real Madrid wrestled La Liga away from Pep Guardiola in his second spell at the Bernabeu and in his second spell at Stamford Bridge, it meant the title.
The United boss is continuing to look for further additions, but what he already has - after spending almost £300million since his arrival 14 months ago - is a strong, powerful side that is capable of challenging for the title.
The defeat to Real Madrid showed United have some way to go to compete with Europe's very best, but the Premier League doesn't have a side on the level of Los Blancos, nor Barcelona.
United haven't challenged since Sir Alex Ferguson landed championship No.20 in his final season at the helm. Since then, they have made waves and money off the field and Forbes now rates them as the "world's most valuable soccer team".
But what the Stretford End faithful wants is a title challenge and entertainment. It will be the club's fifth season since Ferguson's retirement and they have finished 7th, 4th, 5th and 6th. Under David Moyes they were mediocre, under Louis van Gaal they were dull and never looked like genuine challengers.
Mourinho brought back the winning habit last term, winning two cup competitions and landing three trophies, writing off the last month of last term domestically to focus on success in Stockholm.
There is room for improvement among their current crop and room for more arrivals.
Come next May, United must be challenging. They don't necessarily have to be champions - after all, there are six sides pushing for the top honour - but they have to be in the conversation.