Comment: Rodgers faces a long wait for forgiveness of Celtic fans as he looks after number one with Leicester move
Within the brutally unsentimental world of high level professional sport, as in life, nothing lasts forever. Not even cocooned, all-conquering feelings of invincibility.
When news broke of Brendan Rodgers' sudden departure from Glasgow to become Leicester City's fourth manager in two years, the sighs of regret drifting around the Antrim Glens were probably audible across the narrow strip of the Irish Sea to Scotland, where a cocktail of anger, embarrassment and shock from Celtic supporters was already shaking wildly.
Their club, currently eight points clear of Rangers in the title race, assumed the only hearts breaking would have been those of their hosts at Tynecastle Park this evening.
As we assess Rodgers' legacy, if there is one consolation for embattled Celtic chief executive Peter Lawwell it is Neil Lennon's eagerness to step in, temporarily, in the hope the Lurgan man can steer the Premiership champions through the final 11 games and eight-in-a-row.
This marriage of convenience will suit both parties for a while. When was the last time two foremost Northern Ireland managers have been involved in such drama?
Rodgers, the self-professed Celtic fan, but not, as it turns out, at the expense of his personal career calculations. Ironically, Leicester's symbol, the fox, reflects the sort of strategic cunning which overshadows this poorly-timed affair. Then there is Lennon, such a fabled figure of Parkhead.
For all the talk of 'feeling at home' in Glasgow, cultural ties and the rest of it, Rodgers was always someone unlikely to confuse standing still on achievements with hard-wired professional instincts. That he has opted to exchange a much bigger club in Celtic with Leicester can only be explained through the prism of finance.
He will have the kind of money to spend on players at the Foxes he could only have dreamed about in the Scottish Premiership.
Mid-table Leicester's income streams easily dwarf those of any Scottish club, but Celtic have £38m tucked away - one explanation of Rodgers' understandable frustration in terms of his budget. Six-month loan deals in January for Oliver Burke, Timothy Weah and Jeremy Toljan could and should have been permanent deals.
A revealing interview as early as last August lent weight to suggestions the 46-year-old was already sizing up an exit strategy. 'Terminado', the succinct view on his own future in the event of Celtic coasting along, much as they had done under predecessor, Ronny Deila.
Celtic's failure to land Hibs midfielder John McGinn as Scott Brown's heir apparent hurt Rodgers and spotlighted the disconnect between his ambitions and those in the club's boardroom.
Objectively, in domestic reaches at least, the former Liverpool boss can hardly be criticised. Gathering up seven successive trophies attests to that. The moulding of young talents such as Kieran Tierney, Callum McGregor and James Forrest into established stars is a major positive of Rodgers' tenure. The latter two players in particular will probably be on Leicester's summer radar.
Free-scoring Moussa Dembele was a superb buy - until Rodgers keenly noted a diminished attitude and subsequently sold the Frenchman to Lyon for €22m.
Naturally, Celtic's flowing, expansive football from the 2016-17 invincibles features prominently too, and Scott Sinclair, a key man in this respect, had his career resurrected by the manager. Rodgers' overhaul of the fitness levels of players he inherited from Deila, captain Brown a prime example. The attractions for Leicester chiefs are pretty obvious.
Like Rangers boss Steven Gerrard, Rodgers shares an almost pathological abhorrence of complacency. The installation of a rock-solid framework was essentially the main factor in Celtic's invincible campaign. To go a whole season undefeated is nearly beyond comprehension, irrespective of it being in Scotland or anywhere else.
While the timing of this is bad for Celtic, there is also surprise at Rodgers' choice of destination.
The Carnlough man is not a particularly modest manager and achieving double trebles at Celtic do give him a certain entitlement, which explains his frustration at not being in the frame for vacant roles at Arsenal and Chelsea. Yet, the King Power Stadium it is.
As far as Lennon is concerned, three previous titles and two Scottish Cups plus an astute appreciation of the club's demands ensure that, for now, Celtic are in decent hands.
It will be at a later date for both club and the 47-year-old to decide if the relationship is to be extended. Having left Hibernian recently, Lennon is sharp on the Premiership scene and will be welcomed by Parkhead pragmatists.
The emotional aspect for the ex-Northern Ireland midfielder when it comes to his connection with the Scottish champions is obvious in a way that never quite convinced with Rodgers. Lennon's impressive thoughts on the game, and the help of assistant John Kennedy plus first-team coach Damien Duff, will help cohesion within this chapter of unfinished business.
Furthermore, unlike Rodgers, Lennon can point to achieving peaks in Europe. The scope of Celtic history is peppered with big European nights and Lennon's side overcoming Barcelona in 2012 is up with them all.
Such demonstrable, powerful occasions can compensate for plodding domestic predictability. Rodgers has respect for many things; the trophies, his presence, the comprehensive coaching ability, but a European imprint is noticeably absent within a sober evaluation of his time at Celtic. Elimination from the Champions League by AEK Athens in August was a particular disappointment.
How will Celtic react at Hearts tonight? There is, unsurprisingly, sure to be extra interest at Ibrox. Rangers have oscillated between inconsistency and vibrancy this season under Gerrard. However, in absorbing all these rapid changes, the Parkhead uproar can offer a tonic to the Light Blues, who remain mindful of their dominant Glasgow derby victory in December. With two Old Firm clashes remaining, anxiety has been amplified and consequently the only appropriate response for Celts - winning games - will do.
Most of us understand how sentimentality is clinically absent across the modern game. Managers come and go. However, as Rodgers, who has gone from Svengali to outcast at Parkhead, is discovering, in reputational terms, timing is absolutely critical. All the silverware now blurred.
Celtic's primary task is to hold their nerve. If Lennon helps keep focus and contributes to another treble then the club will thank him, with Rodgers' guidance hitherto this term, especially since the turn of the year, counting for little in comparison.
Lawwell may not even opt to look elsewhere for a longer-term manager, although that would make him more unpopular with sections of the support.
Perhaps, at a much later date, Rodgers will be cut some slack in regard to his Celtic era. One suspects it will be a long wait. For it is clear this window of opportunity in the Premier League was a restricted one - and, frankly, the Ulsterman who accomplished everything Scottish football could offer, was looking after himself and no one else.