The game’s only goal came 10 minutes from half time, via the only United shot on target during the 90 minutes.
It was fitting that Michael Carrick was heavily involved in Marcus Rashford’s goal, floating an offside trap-beating pass over the Hornets' defence to pick out Juan Mata’s well timed run.
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Mata could have shot himself, but he squared unselfishly to Rashford, who slid the ball home into an empty net with Heurelho Gomes stranded.
Jose Mourinho opted to field a team packed with fringe first teamers and you get the sense that many of them shared a last appearance in red alongside Carrick.
Daley Blind and Matteo Darmian in particular look certain to depart before the World Cup. With little action to speak of on the pitch, the intonation of the Old Trafford crowd at least made for some compelling listening off it.
There were messages of support for Sir Alex Ferguson along with numerous renditions of Carrick’s song.
There were also plenty of second-half groans aimed at the United players who wasted successive chances to mount counter attacks.
Poor first touches and passes poor in execution and choice scuppered move after move. It meant that the United supporters sat through their last 45 minutes of league action for the season without a shot on goal to cheer.
United did win the game however, pushing their points total for the season past the 80-point mark for the first time since their last league win in the 2012/13 season.
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Has this season been a success?
Winning or not winning the FA Cup next weekend against Chelsea will have a huge bearing on how this season is measured in terms of success. If we are strictly talking about the Premier League then, from a statistic standpoint, the season has been a successful one.
United collected their highest total of league points since they last won the title. Similarly, they have recorded their highest number of wins and scored their highest number of goals since the 2012/13 campaign.
Results against the teams in and around them have improved too. The numbers look healthy, but we are football and not spreadsheet fans.
The actual football, by and large, has been really tough to watch. Of course, the Champions League exit to Sevilla has been difficult to shake off too.
Are you happy with your manager?
In short, no. When Mourinho was installed as United manager, I think the majority of supporters accepted that the club had sort of backed themselves into a corner somewhat.
There weren’t really any other viable candidates for the job at the time and Mourinho was available. When Jose was appointed, United fans seemed content but concerned.
They worried about Mourinho’s style of play – that it was too defensive and not in keeping with United’s attacking traditions. They worried about his track record of throwing his players under the bus when things went wrong on the pitch.
They also worried about the potential marginalisation of United’s younger players, with Mourinho’s long-standing reputation for favouring footballers in their prime.
Unfortunately, all three of those concerns have been realised. United’s style of play is turgid and the team probably play the worst football out of any “top” team in Europe – that’s not hyperbolic by the way, go watch the others.
Mourinho has slaughtered his players publicly on more than one occasion this season and it looks as though it’s had a negative impact on the squad.
Starlets Anthony Martial and Rashford had their wings clipped after Mourinho opted to throw sacks of cash at 29-year-old Alexis Sanchez.
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Martial is set to leave, while Rashford is rumoured to be unhappy. Luke Shaw has been messed around too.
Scott McTominay is the only exception, though it’s no surprise to see Mourinho choose to blood the tallest, strongest kid at the club over the more technically gifted ones.
The summer break has come at the right time for Mourinho, but if the football doesn’t improve right from the get go next season, the pressure from the stands will start to ramp up.
What should be the club's priority in the transfer market this summer?
Where do I start? Mourinho is getting very little out of this squad. But the question is - are the players simply not good enough or is the manager failing to motivate and organise them properly?
The full-back and centre-midfield positions quite obviously need some strengthening. United have been linked with Alex Sandro and Kieran Tierney at left-back, while the media are suggesting that Jorginho, Fred and Sergej Milinkovic-Savic have been identified as midfield targets.
Personally, I think United are crying out for a right-sided attacker than can beat men in one-on-one situations, though Chelsea’s Willian, approaching 30, would be an uninspired pick for that role.
A top, reliable centre-half who can keep himself fit for the entire season should also be high on the shopping list. Toby Alderweireld has been touted as a potential signing in that area, but again his age has got to be a concern.
That’s half a team already. I’m not sure we should be at this point having splurged £200 million plus under Mourinho inside two years. Something is going drastically wrong.
What do you want to aim for next season?
Enjoyable football – that’s it. Yep, it really is that simple. United supporters want to look forward to games again. They don’t want to build their weekend around going to or watching the game, only to have the excitement sucked out of them inside 20 arduous minutes.
United have some really talented players and if they play good football, they will win the majority of their matches. Sadly, the kind of football we want is the kind of football Mourinho is unable to provide.
With Rui Faria leaving and a gap opening up at Mourinho’s right-hand side, there is a hope that a more tactically adventurous member of staff might be added to Jose’s backroom.
But in terms of optimism for next season, that’s about it. The prospect of watching another year of Mourinho-ball is like being handed a sentence to be served.