There is a certain cosmic irony in Spurs, the perennial nearly-men of English football, lifting European silverware in a season where their league form collapsed like a soggy soufflé.
Yet, here we are.
Postecoglou, the gravel-voiced Aussie philosopher of possession football, has guided the London side to their first continental trophy since 1984. And in doing so, he's handed controversial chairman Daniel Levy both a lifeline and a dilemma.
Let's get the good stuff - at least for Spurs fans - out of the way: Tottenham won the Europa League.
No, seriously. In a campaign where their Premier League ambitions imploded faster than a lead against Chelsea, Postecoglou somehow masterminded a run through Europe that culminated in a 1-0 victory over Manchester United in the final at San Mamés Stadium in Bilbao.
Tactically, the Australian's signature high line and intricate attacking transitions finally clicked against continental opposition.
Spurs averaged 1.87 goals per Europa League match, with Brennan Johnson scoring the decisive goal in the final. The data tells its own story: Tottenham's Europa League campaign was marked by resilience and efficiency, contrasting sharply with their domestic woes.
In the Premier League, they averaged 1.68 goals per match and managed only six clean sheets in their 38 games, second only to the 2003 and 2023 seasons, where they kept only five.
They kept six clean sheets in just 15 European games this season, including in a relatively low-key final in Bilbao against a very impotent and seemingly broken Manchester United.
Too little, too late?
Yet beneath the silver gleam of the trophy lies a season of contradictions.
Spurs finished 17th in the Premier League, their worst top-flight finish since the 1976/77 season. It's their lowest ever finish in the Premier League era.
Lower than the traumatic days of Christian Gross's leadership.
Lower than the uncomfortable reality of having Ian Walker as a first-choice keeper.
Lower than when their main attacking threat was an Irishman named Gary Doherty, a centre-back masquerading as a striker and affectionately, if self-deprecatingly, known as the 'Ginger Pele'.
They conceded 65 goals, went winless in eight of their last 10 league matches, and failed to beat a single top-six side after Christmas. It was, by domestic standards, a collapse - especially considering the impressive start to life he had made just the season before.
Spurs had some horrendous injury misfortune, particularly in defence: Postecoglou was only able to field a first-choice backline of Guglielmo Vicario, Destiny Udogie, Micky Van de Ven, Cristian Romero and Pedro Porro on eight occasions in the Premier League this season.
But they still lost three of those matches, and only won half.
The hard truth is, in any other season in English top-flight history, Spurs would have likely been relegated.
No room for sentiment
Now, Levy faces a moment that demands cold clarity, not sentimental delusion.
Yes, Postecoglou has delivered European glory, but if Manchester United taught us anything after their shock defeat of City in the 2023/24 FA Cup final, it's that silverware can be a smokescreen.
Erik ten Hag's brief reprieve after lifting the cup only delayed the inevitable. United sank deeper, clinging to hope while the structure continued to rot around all areas of the club.
The Red Devils, blinded by their first meaningful contribution to football in yonks, activated a year-long extension to the Dutchman's contract the following week, mainly due to fan pressure and a distinct lack of available managerial alternatives at the time.
By the following October, just three months later, Ten Hag was gone, with the club sliding even further down the table to 14th in the Premier League with just three wins from their opening nine matches.
By that time, it was difficult - maybe even impossible - to shift any dead weight, begin a rebuild and make any progress back up the table under new boss Ruben Amorim, who didn't necessarily even want to join at that moment in time. Remember, the Portuguese coach had originally requested to leave his Sporting post at the end of the season.
Despite them also somehow fudging their way to the Europa League final, United were probably the one team Spurs could feel confident playing against, having already beaten them three times during the season.
A form anomaly
Much like Ten Hag's FA Cup win, Postecoglou's Europa League run was exhilarating, but it was also isolated - a tale of knockout heroics divorced from week-in, week-out domestic inconsistency.
His league tactics were soon sussed and repeatedly exposed by pretty much everyone (except United), his defensive structure was porous, and his inability to adapt against pressing sides was troubling.
Of course, injuries played a part, as did a lack of competitive transfer activity that focused on the here and now from Levy. But you work with the tools you are given, and Postecolgou will have been aware of Levy's traits before joining.
To reward one good month with another year of potential underperformance would be foolish.
Ange has won hearts
This is not a call to ignore what he achieved. Postecoglou deserves thanks, plenty of plaudits, and maybe even a statue outside the club museum with a bronze-cast speech bubble attached, reading "Mate"; however, another season at the helm seems too risky.
Spurs - both the club and fans alike - might wish to be ruthless, not romantic.
Because if there's one thing football fans have learned from the Erik ten Hag saga, it's that the worst rebuilds are the ones that never start.
Levy has the chance to learn from United's error: don't let a trophy cloud your vision.
Begin the next chapter now, with a manager who can build across all competitions (which now miraculously includes the Champions League), not just ride the adrenaline of the previous campaign. The soufflé, sadly, is already flat.
'Big Ange' has earned his flowers. He's won the hearts of Spurs fans forevermore. He now has the power to deliver arguably the greatest mic drop in English football history after consistently backing up his claims of "always winning in a second season".
He can walk away with his head held high and reputation in better stead than it might've been, while Levy has the trophy that might get fan groups and protestors off his back for a little while as he lines his and his bosses' coffers with the prize money.
What Levy must do, however, is back the next manager in what will no doubt be a riveting transfer window for the Londoners, as they seek to add to what, on paper at least, looks like a decent squad boasting a few exceptionally talented youngsters.
Just don't go asking Sir Jim Ratcliffe for advice on what to do.
