On 5 November, leaders Rangers had just moved 15 points clear of third-placed Celtic in the Scottish Premier League after beating Dundee United and the defending champions looked a great bet for a fourth successive title.
Celtic had two games in hand, but their form had been faltering and as they prepared to take on Motherwell, who were three points above them, questions were being raised about Neil Lennon's side's ability to make serious inroads into that deficit.
Fast-forward seven weeks, and Celtic have put together a domestic run of eight straight victories, starting with a 2-1 win that day at Fir Park, and closed to within a single point of their fierce rivals, who themselves have stumbled and lost their invincible aura away from home.
The loss of Steven Naismith to injury has been fundamental to that, and while that has been discussed at great length, it cannot be overstated such was the Scotland forward's importance to the Rangers cause.
Rangers are not entirely bereft of creativity in Naismith's absence - Gregg Wylde, Sone Aluko and Steven Davis are all capable in that regard - but there is no question they are now less able to open teams up, and Davis's own form has faded in recent weeks.
The skipper has shouldered plenty of responsibility over Rangers' championship-winning seasons and the absence of fellow-talisman Naismith has added further to that.
With high-quality options lacking for manager Ally McCoist, if Davis is not playing well, Rangers struggle to tick.
And while the Ibrox side have hit a rut, Lennon's men are well and truly out of theirs.
It is difficult to pinpoint the reason. Lennon himself says he did not change anything in terms of his approach to games, or to training.
He also admitted he wondered at half-time in the Kilmarnock game, when his side trailed 3-0, whether he would be able to get the club back on track.
Of course, that game finished 3-3, and though Celtic were to stumble again, in a goalless draw at home to Hibernian, that result would appear to be pivotal to Celtic's change of fortune.
They have certainly tightened up defensively - the late goal scored by Dani Racchi of Kilmarnock on Christmas Eve was the first they had conceded in five SPL games.
Georgios Samaras has hit good form playing wide on the left, James Forrest looks dangerous and lively on the opposite flank and Gary Hooper is scoring regularly.
Victory on Wednesday evening will put them ahead in the title race for the first time this season, and the form book would suggest that is what will happen.
Many veterans of Old Firm battles, though, will tell you form is meaningless when it comes to Old Firm games.
Wednesday's game is set up intriguingly and, as usual, it would take a brave man to cast a prediction either way. Yes, Celtic are on a better run and yes, they are favourites. But Rangers have not won the last three league titles by paying heed to the bookies' forecasts.
Either way, 28 December could prove to be a pivotal date in the race for the title.