The result may have been meaningless as Arsenal again crashed out of the Champions League in the last 16, but the performance was anything but. The Ox was hugely impressive...
Manuel Pellegrini's side must seek an early goal that will cause panic amongst home supporters (and then hopefully players) in the Camp Nou. It may be a thankless task...
* UNITED BACK IN THE TITLE RACE! Well, probably, but that doesn't mean they were particularly good in beating Arsenal - they did enough, and not a huge amount more. The result had more to do with Arsenal being mediocre and offering virtually nothing by way of penetrative attacking play than it did to anything spectacular about United.
That might be slightly unfair - United's defence was excellent, but in the second half in particular they gave too much of the ball to Arsenal, and in some respects were just lucky that the visitors didn't do a great deal with it. One imagines that they will have to play much better in order to retain their title, but on a day when two other theoretical title contenders lost limply, perhaps just enough will be, well, just enough.
* So what to make of Arsenal? Before this run of tough games, much was said about what it would say about their true strength, and whether they can be considered true title contenders. Well, the results are now in, and they are...inconclusive. They recorded a win and a defeat against Borussia Dortmund and a win and a defeat against Liverpool and Manchester United. Not much can be read into the Carling Cup defeat to Chelsea because of the amount of changes Arsene Wenger made to his side, but after this run of fixtures all we can really say is that while Arsenal are as close to the 'real thing' as they have been for a few years, they aren't there yet.
* This game shouldn't necessarily lead to further questions about their mentality, especially just days after their win in Dortmund. This was a close game, with the teams essentially separated by how their defences dealt with crosses, so Arsenal shouldn't be put back into the box marked 'spineless goons' just yet.
* That said, this was the sort of game that would form part of the evidence for anyone making the case against Arsenal's title candidature. Not necessarily just because they lost, but when Wenger looked to the bench for someone to change things, give them some impetus and hopefully get them a goal, he told Nicklas Bendtner to take his trackies off. Sure, they have injuries, but their paucity of striking options is obvious and could be decisively costly.
* As we've said before on F365, Olivier Giroud should be an option rather than the option for Arsenal. In games such as this, he is too slow and his relative inability to create something on his own hampers Arsenal greatly. It's an obvious point to make, but they need a striker in January, whether that's to replace Giroud permanently, replace him occasionally or simply support him. The good news for Arsenal fans is that Ivan Gazidis seems to recognise this, and while talk of signing Karim Benzema might be fanciful, all signs are pointing to recruiting a forward when the transfer window opens.
* Has Mesut Ozil actually been that good for Arsenal? It is of course obvious that he is a class player, and once or twice every game he does something that will make any Gooner make a funny little noise of pleasure, but in how many games has he been the decisive player? Few, if any, and he certainly wasn't that player against Manchester United. He has perhaps 'lifted' the club, and offered some other form of intangible boost to the rest of the squad and their fans, but his contributions have thus far been relatively peripheral. Of course this is not to say that Arsenal wasted their money by buying Ozil - far from it - and the chances are he will grow back into the player that was so brilliant for Real Madrid, but Arsenal's exceptional start to the season has not been directly down to their record signing.
* You'll probably read plenty about how well Wayne Rooney played (not least in our match report which, we should say, is not written by F365 staff), but it was one of those classic occasions when he didn't actually do much tangible, particularly with the ball (with the exception of his excellent corner for Robin van Persie's goal). What he did do was run around quite a lot and made some decent tackles, which is pretty good but not really what he's there for. Still, Rooney running around a lot when not especially in form is a step up on some games last season, when during similar games he just ambled around a bit and generally looked like he would rather be somewhere else. So that's something.
* Far more worthy candidates for the man of the match award were Phil Jones (more on him shortly), Patrice Evra and Chris Smalling. The highest compliment that can be paid to the latter man is that United didn't miss Rafael at all.
* Said Wenger of Robin van Persie this week: "Of course it's strange for me to see him in a United shirt because for me he's an Arsenal man. I took him when he was a very, very young player. We have gone together through very difficult periods and he became a world-class player and for me he is an Arsenal player."
He didn't look like much of an Arsenal man with the veins bulging in his forehead after scoring there, Arsene.
* Incidentally, Van Persie quite rightly celebrating with the fervour of a man scoring against the league leaders simply highlights the stupidity of the 'muted celebration' - he apologised to the travelling Arsenal fans 'out of respect' when he scored against them last season, so why the difference now?Does 'respect' have a one-year shelf-life? Is it only in the first game against your old club that you have to be deferential? Or is it all self-important bollocks?
* The exclusion of Adnan Januzaj was a puzzling one. The assumption about his omission from the trip to Real Sociedad in the week was that Moyes was resting his young winger for the more important game, but unless Januzaj picked up an injury or was ill (and his presence on the bench would seem to point away from that), the decision to start Shinji Kagawa in his place was an odd one. Was it because Moyes thought it was too big a game for an 18-year-old? Is this the United manager's instinctive conservatism kicking in again? Januzaj's regular inclusion in the United team this season suggested that he had moved away from such thoughts.
Moyes may indeed have decided to counter Arsenal's relatively narrow midfield with his own, but their superiority in that area was not down to the Japanese playmaker. Kagawa was fine - he didn't do much wrong, but didn't do a huge amount right either, and one might argue that United would have benefited from the more direct threat that Januzaj would have provided.
* That midfield control certainly changed in the second period, after Phil Jones dropped back into defence. Jones was excellent in the ball-winning, run around everywhere role alongside Michael Carrick, so it was therefore curious that when Nemanja Vidic had to go off and Jones retreated, Moyes chose to bring Tom Cleverley on rather than Marouane Fellaini. The physical presence in the middle clearly made a difference, so bringing on a 5 ft 9 midfielder who only passes the thing sideways was curious. It was hardly a surprise therefore, that Arsenal dominated possession - not that they did a great deal with it - after the break.
* Arsenal's first-half performance was strikingly similar to how they played in the opening 45 minutes against Dortmund in the week. They created absolutely nothing in attack on both occasions, but in Germany it was hailed as a first-class rear-guard and masterpiece in playing on the road because Dortmund didn't score. United did, so Arsenal's impotent efforts going forward looked even more desperate. Wenger's old friend sterile domination again.
* Ah the debate about zonal marking, our tedious old friend. One thing that occurs is why the Arsenal defensive line didn't initially station themselves a yard or two deeper, so they could get a better run on the ball. As the Sky pundits pointed out, it's obviously easier to win a header with some forward momentum, and Van Persie profited from Giroud and Thomas Vermaelen almost defending from a standing start. Even without that, one wonders if Arsenal's former striker would have found it quite as easy to nod/shoulder in had Per Mertesacker been guarding the near post, rather than Vermaelen and Giroud.
* We've seen some pretty ludicrous refereeing decisions in recent weeks, but the yellow card given to Jones for colliding with Wojiech Szczesny is right up/down there with the worst of them. The man was looking the other way, towards the ball, when they clashed heads. The only reason Jones wasn't similarly hurt was because he is apparently impervious to human pain. The first footballer ever carved straight from a potato.
* Nicklas Bendtner could have done with a rather better performance...actually, scratch that - a 'not comically appalling cameo' after saying this.
Nick Miller - follow him on Twitter