A blue moon, as we all know, is a rarity. What not everyone appreciates is that it most often arises (so it says here) following such monumental occurrences as volcanic eruptions or especially large fires.

No doubt each of Diego Costa’s seven goals this season is, to the minds of Sky’s marketing men, an event of similar magnitude. But should the collection be given the pre-match montage treatment this Sunday, Manchester City’s famously soothing ditty would hardly seem a fitting soundtrack.

The ferocity with which the Brazilian-born Spanish international has propelled himself to the forefront of the Premier League picture this season may make him just the man to see to it that the Eastlands citadel is stormed, not once in a blue moon, but twice in as many attempts.

Manchester City’s home league record since Chelsea became last term’s first victorious visitors at Etihad Stadium in early February reads: won 7, drawn 1, lost 1, Goals For 24, Goals Against 6. That is impressive, if not imperious, until you consider that the single major blip came against unfancied Stoke City just last month.

That day, the industry and tenacity of former Manchester United frontman Mame Diouf did for the Citizens and Chelsea will hope that their £32m summer signing, who boasts those two attributes in abundance together with several notable others, will enjoy similar success.

Having been benched for the midweek action, as both sides suffered setbacks at the hands of German opposition due in no small part to a lack of firepower, Costa will seek involvement on the bright side of the white lines and at the business end of the field. His manager all-but-declared him a starter after the Schalke match in the wake of a rusty Didier Drogba display and, at 25, his tender hamstrings aside, he is entering what is likely to be his striking prime.

There is no shortage of competition to push the ex-Atletico man on, with Loic Remy scoring on debut at Stamford Bridge in the win over Swansea City. What he also cannot bemoan is a lack of suitable staging from which to showcase his talents. Last week it was 1st plays 2nd, this time Champions v League Leaders is the back page caption as all eyes once again focus on Jose Mourinho’s juggernaut as it surges into town to face a further test of its capacity to lead the trophy chase.

Last season talk was of buses being parked by Mourinho at Etihad Stadium and beyond. But the work of his team thus far this campaign has sought to debunk the myth that the manager’s sides are set up in an overly pragmatic and passive manner.

Chelsea have notched 15 already this time around with just 360 minutes on the clock, their new talisman alone bludgeoning and badgering his way to that gobsmacking figure of seven before Halloween decorations hit the shops.

By contrast, City – who last year came within one of their guests’ record Premier League tally of 103 – have found things relatively tough in the final third and are winless in their last three in all competitions. The absence of Alvaro Negredo and, more recently, the in-form Stevan Jovetic has not exhausted the patience of manager Manuel Pellegrini, however, in aiding the steady return to fitness of star man Sergio Aguero. The Chilean’s commitment to nurturing his key player is to be commended, following a lay-off from which his protectee was never allowed to fully recover amidst a gruelling summer schedule negotiated while serving his country.

The Argentinian was also missing in February, when Branislav Ivanovic’s breathtaking low drive decided this fixture for the forwards, Samuel Eto’o hitting the woodwork along with Nemanja Matic and Gary Cahill in a game that said much about the away team’s solid base and unspectacular firing line that would ultimately lead to the team falling just short of the title three months later.

It will be intriguing to see if the high-octane, almost cavalier approach of that evening is replicated on Sunday or whether, with his side having conceded six times in their three most recent outings, the Portuguese reverts to the style that so stifled and suffocated then-title rivals Manchester United on his other league visit to England’s unofficial second city during a similarly embryonic phase of last season.

Much may depend on the supply line to Costa from Cesc Fabregas – who notched his own inaugural effort in blue on Wednesday – and Eden Hazard, man of the match in this fixture last season, who celebrated his new £200,000 per week deal, rumoured to be in the pipeline, on Wednesday with an equally worthy performance despite the disappointment of dropped points.

In the end, it may just be that fortune simply favours the brave. Will the ‘Special One’ select his secretly vulnerable spearhead to outfox his opposite number once again? Or is ‘the Engineer’ set to at last construct a wholly balanced and coherent system featuring two out-and-out strikers in tandem?

Here’s to hoping for an on-fire forward to prove the difference. Is that asking for the moon?