After the 2-1 win over Liverpool on Saturday it seemed, at last, as if Manchester United might have turned a corner.
They have been fine without ever really being great all season. The Premier League table is testament to that, with United well off the pace of the champions-elect City but now holding a five-point advantage over third-placed Tottenham.
That win should have been enough to spark them into life. It should have been a season-defining result. It should, at the very least, have injected some confidence into their players.
But, on Tuesday night, a ludicrously unambitious performance against a Sevilla side 27 points off the top of the La Liga table saw them crash out of the Champions League in shameful fashion.
Old Trafford was half empty by the time the whistle blew at the end of the game; despite Romelu Lukaku's fine volley, there was little hope of a comeback. There was no reason to believe United were capable of it.
United pale in comparison to swashbuckling Spurs
It was a stark contrast to Spurs' own home defeat last week, which consigned them to the same fate.
The black-and-white facts are that both sides are out of Europe but Spurs crashed out with their heads held high, playing with verve and panache against one of the best sides in the world who, in the end, were just a little too good for them.
Looking at United's potential team sheet, there is no reason why there should be such a chasm between the sides. Romelu Lukaku, Alexis Sánchez, Anthony Martial, Paul Pogba, Marcus Rashford, and Juan Mata should be among the most terrifying attacks in world football.
Sevilla weren't scared. As defender Simon Kjær claimed after the game, they knew that United would create chances 'by coincidence' but they were confident of holding them off for the most part.
There is one cause for their impotence in attack: José Mourinho.
Questions but Mourinho doesn't have the answers
When the Portuguese moved to Manchester having lost 9 out of 16 league games with his own title-winning Chelsea side, it seemed a fairly obvious choice.
Mourinho had been flirting with his new club for years and was probably still the biggest name in world football management; he might not bring glitz and glamour but you could be assured he would bring a dominant presence to the dugout.
Last season, things were uncomfortable but his habit of winning trophies continued and, to some extent, satiated the fans. It was not a great season, as a sixth-place finish testified but two cups were a decent enough return.
This season was supposed to be the year it all came together. Instead, Mourinho has resembled a man who has realised he has lost half the pieces of a jigsaw and is desperately pulling pieces out of other puzzles at random to try and finish it off. A midfielder here, a winger there - it should all work out.
His squad is the envy of managers around the world but his first eleven is still unclear. Almost two years into his reign, having spent the GDP of a small nation on transfer fees and aiding the construction of a Scrooge McDuck-style diving pool of coins at the Sánchez residence, this is not good enough.
More and more, Manchester United are starting to look like an unfortunate caricature of the 'Zidanes y Pavones' at Real Madrid. They have the big names and in Marcus Rashford and the emerging Scott McTominay, they have the home-grown heroes too. But there is nothing resembling a grand plan, an end product in mind.
Tactical outlook is behind the times
To his credit, Mourinho set up his side against Liverpool very well but this is an exception rather than a rule in a season where his players have saved him with moments of quality, rather than having him to thank for his tactical decisions.
An exercise in the hypothetical might be of use here. Imagine a set of talented young footballers, losing their way as a group but each possessing the ability to do wonderful things on their own. A former PFA and FSF Player of the Year has just joined them, freed from the shackles of what had become an uncomfortable situation at his previous club. They just need a manager.
In the year 2018, would José Mourinho be your first choice? It's not likely.
All around the Premier League, evidence of his decline as a manager is waving and hollering, trying to make itself clear. His great rival, Pep Guardiola, is in with a shout of breaking the Premier League points record on the other side of the city.
Three talented young players, in particular, were let go during his most recent Chelsea spell: Kevin De Bruyne, Mohamed Salah, and Romelu Lukaku.
De Bruyne and Salah are the league's standout talents. Lukaku, back under Mourinho's guidance, is ten goals behind the Golden Boot pace-setters, having pushed Harry Kane all the way last season while playing in a dysfunctional Everton side.
Liverpool and Spurs are playing some of the most attractive football seen in England in recent years and, while they might currently be behind United in the table, they will remember this season with far more fondness than will the fans at Old Trafford.
Arsenal are evidence of power of mismanagement
Ominously, Arsène Wenger continues to steer the Good Ship Arsenal from disaster to disaster, an enduring symbol of the damage which can be done by a stubborn manager stuck in outdated ways.
Transfer policy, starting eleven, tactical decisions: it all comes down to Mourinho. He is, in a way, lucky to have a player in Paul Pogba who attracts attention with his every touch.
But despite only playing half an hour against Sevilla, having been injured at the weekend, Pogba was once more the subject of fans' mockery and ire on social media. He has been a useful human shield for his manager this season but there is little doubt that Pep Guardiola, Mauricio Pochettino or Jurgen Klopp could get more out of him.
Whether Manchester United will pull the trigger having handed Mourinho a new contract only a few months ago remains to be seen. If they can keep hold of second place, it would seem unlikely, particularly if they win the FA Cup as well.
But Manchester United can do better. And when a club of their stature can do better, they should do better.
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