Other than indigestion, Christmas guarantees nothing. In football there is sometimes the rumble of satisfaction at being near the top on December 25, but for Carlisle United it must now be about fighting like tigers to protect what they have.

The Blues head to Crewe on Monday in a fine position: second in League Two, seven points above the play-off places: hopefully a cushion against any slips, and protection against the injuries they are currently carrying.

Assuming it is simply a matter of consolidating promotion from here is, though, risky business. It would be an unfortunate 2017 indeed if United do not reach May in the top seven as a minimum, yet the work to be done to make sure of that remains considerable.

The good news: history suggests they should remain around the front of the pack. In Carlisle's 70 post-war seasons their position at Christmas has changed by an average of just three places come the end of the campaign. In other words, Keith Curle's team can be predicted, broadly, to finish no lower than fifth, hopefully higher.

Further encouragement: when a Blues side climbs towards the top of the tree, they don't tend to fall too far. In 2005/6 they converted third at Christmas to first by the end. In 2004/5, second became third; in 1996/7 the same. The table-toppers of 1994/5 remained so until May, the promotion-hunters of 1981/2 finished second after leading at Yuletide. Alan Ashman's boys of 1963/4 were second when the turkey was served and still there when spring came.

So there is a decent record of seeing the job through. But that does not mean a good start is destined to bring a good finish every time. Carlisle's history also includes a couple of home-straight falls that would have embarrassed Devon Loch, a few disasters with glory in sight that could keep Don Fox company.

Circumstances, events, an inability to last the course: they have stalked United here and there. In 1959/60 they plummeted 13 places, sixth to 19th, between Christmas and the final day. Then there was arguably their most infamous nosedive: in 1989/90, a season that began, like this one, in record-breaking fashion, but then went alarmingly sour.

Going over the archives of that particular campaign brought the need for a strong drink and a counsellor close by. The old pages told how a potentially magnificent Carlisle campaign unravelled, inch by inch, and even as the spool had almost emptied itself completely there was still time for one of the worst finales imaginable.

Carlisle topped the Fourth Division at Christmas that season and it is further bracing to think that, when Clive Middlemass and his players woke up on March 5, they were still looking down on the other 23 clubs. That status had, alas, become deceptive, and by the end of that day a form slide had become terminally damaging.

After beating second-placed Exeter in front of 8,432 fans on an expectant Tuesday night in February, going four points clear in the process, Carlisle lost their next six games, scoring just once. The toll was being taken by season-ending injuries to key players John Halpin and Ian Dalziel and when suspensions and further injuries then totted up, it must have felt like some higher force was out to sabotage everything good.

Footage of one of those mid-collapse games is on YouTube, a 2-0 defeat at Southend which gives a clear window onto things going inexorably wrong. There are two red cards (brandished by future top-flight ref David Elleray), some golden chances missed, a couple of avoidable goals conceded, and overall it is tempting to wonder whether the banner in the away end - "Carlisle United no to I.D." - was less a protest about Margaret Thatcher's identity card plan than a wish to conceal everyone's involvement in the sorry decline.

At one stage in a congested run-in Carlisle had just 13 available professionals and had to give a 17-year-old, Rob Edwards, his debut. He eventually flourished but in an extremely tight division Carlisle found themselves eighth just 12 days after they had been first.

An attempted rally from there did not catch enough momentum, possibly not helped by the £20,000 deadline-day sale of goalkeeper Dave McKellar and his replacement with Bolton loanee Kevin Rose. Chairman Andrew Jenkins made what now sounds quite a familiar appeal for support, stressing that the club was "on a much sounder footing financially", and while that did not necessarily stand up to scrutiny over the following couple of years, one cannot help but wonder what a promotion in 1990 might have done for the city and its club.

Infamously, it didn't happen, because even on a last day when defeat at Maidstone would not on its own have guaranteed failure to make the play-offs, Carlisle conspired to finish outside the top seven, thrashed 5-2 and then trumped on goal difference by Chesterfield, who beat Grimsby in a game held up 15 minutes by crowd disturbances.

That last quarter-hour, with players in the dressing room desperate for news from Saltergate, sounds akin to the waiting room at a funeral. Afterwards, the News & Star 's Tony Smith described the hollow scene: "The faces of the United players, as they sat outside the Watling Street ground in the late afternoon sun waiting to board the coach for the long journey home told the story of a day of disaster for the club."

Middlemass, the manager, said it had felt worse than the time he was told his career was over after a car accident. The truth is that Carlisle had lacked the goals, and the back-up, to cope when misfortune struck, and what had energised the place through the autumn had always been more precarious than it had looked.

These stark memories stand out because they are so rare, but if there is a message at all it is to make sure what you are building has foundations that can survive an ill wind.

By game 46, each season will have set an unrivalled examination of what you have and what you don't. Curle's squad is small, even if it has greater depth than what we have just recalled, and in the short term it will be about how it rides immediate injuries and plugs any necessary gaps.

That way we will know whether the festive bubbly can come back out in May, as it should.