Do Manchester United have a derby problem?

Manchester United go into Sunday's derby in pretty good form: since February's disappointing loss against Swansea City they've won five on the spin, including a surprisingly comprehensive dissection of Tottenham and a profoundly enjoyable afternoon at Anfield. City, meanwhile, are teetering on the edge of one of modern football's Miracle-Gro crises: out of nothing they've lost their last three away games, effectively abandoned their title and slipped from second to fourth in the table. "Pellegrini out?" articles proliferate like weeds.

But. This is a derby, and if everybody knows one thing about derbies is that form is not to be given its usual weight. The metaphorical form book is to be taken, weighed in the metaphorical hand, then hurled through the nearest metaphorical window. And while United might be in a pretty good mood at the moment, when it comes to thi particular fixture, their recent record has been utterly miserable.

In fact, it's been historically miserable. United have lost the last four games against their cross-town brethren — 2-1 at Old Trafford at the end of the 2012/13 season, 4-1 at the Etihad and 3-0 at Old Trafford during the Moyes interregnum, and then 1-0 at the Etihad earlier this season — which amounts to the worst run of consecutive derby results in history. Though there have been longer winless streaks, including a run of seven games between 1968 and 1970, and five losses in six games between 1952 and 1955, that row of L, L, L, L is (tBB thinks) unprecedented.

So, as human beings in possession of a pattern, we have to ask ourselves: is there a deeper problem at work here? Have United — who are generally quite a good football team, even when they're not — developed some kind of derby-specific phobia over the last couple of years? Have they — unthinkably, unforgivably — ceded the city to City?

Probably not.

The idea that a derby game is somehow isolated from its general context is pervasive but not entirely persuasive, and of our small sample here, only one of those four losses has been out of keeping with the general form of both sides. Though both came early in the season, City were in better shape for both Louis van Gaal's and David Moyes' first derbies, and by the time Moyes' second rolled around, City were on the way to the title while United were lying on the ground in a foetal ball, begging for everything to stop. In short, in the last three derbies the better team before the game, in terms of league position and wider form, has been the winning team afterwards. That's not a derby problem (though it is obviously a United problem). That's just the way of the world.

The oddity is Alex Ferguson's final derby, way back in 2012/13. (Okay. But it seems like ages ago.) This game fits right into the Derby As Exception theory: the stronger team strolled up a yard off the pace, while the team with nothing to play for found something. It meant nothing in wider terms — that win cut United's lead at the top of the table to a mere 12 points, and they ended up winning the league by 11 — even if it was a largely uninspiring hour and a half. But given that United had dismantled City at their place earlier in the season, we can't necessarily draw too many conclusions.

There's not much devil in the details, either. Ferguson's last derby side played like a side who were 15 points ahead and knew it, Moyes' boys were eviscerated twice, and Van Gaal's team were undermined after half an hour by a red card of quite remarkable stupidity from Chris Smalling. Indeed, the last half hour of that game was quite encouraging from a United point of view, in a futile sort of a way. Certainly, City never looked as comfortable against this season's ten men as they did against last's eleven.

It's an odd thing that happens a lot in football: the presumption of patterns across seasons. Team X haven't beaten Team Y for five games, six games, or whatever. Such runs of results might have significance when when there's consistency of personnel and style on both sides, as in Ferguson's last few seasons when he basically figured out how to beat Arsene Wenger's Arsenal. But generally, football is too chaotic for this to make much sense: the last four Manchester derbies have been overseen by five managers and involved 48 different players.

Ultimately, if United are suffering from a derby problem, it's a remarkably virulent one that presents a huge variety of symptoms. It's a problem that extends to demotivation when winning a title, disorganisation when falling to pieces, and dipstickery when rebuilding; one that affects both Wayne Rooney and David de Gea, present in all four recent losses, and Marcos Rojo, who made his derby debut last November; one that has affected three managers of markedly distinct personalities and approaches. One that looks, once you break it down, suspiciously like three different types of underperformances, each belonging to a different manager, all of which just so happen to have turned up in a row.

Not that any of this helps, of course. Derby disappointments feel more significant because derby games are more significant. Perhaps that's why there is always the suspicion that a limp performance in a derby is something to do with the players not being up for it: these are the games that weigh heavier on the heart, and so there must — surely! — be something more complicated going on than 'the other lot were better'. Maybe that's why these games are so often assumed to sit outside the normal pitch and yaw of football form.

If United burst out of the traps this Sunday and annihilate City — annihilate carefully, of course, with considered use of possession — then there will be no problem. If they lose, however, and even if they lose in a bizarre fashion entirely out of keeping with the preceding four losses, then it will be five in a row and the problem will be swelling. That United may not actually have a derby problem is immaterial: if they keep losing them, it will feel like they do. And that, ultimately, is what matters. Derbies matter too much for the normal rules to apply. Logic follows the form book, is dispatched to the metaphorical pavement below.