It may well have been the best Celtic performance in Europe of the 21st century.

Sure, the Parkhead side have claimed the scalps of much bigger opponents over the years, weaving far more specular David and Goliath fables into the tapestry of club folklore.

Barcelona, for one. Manchester United, another. AC Milan. Lazio. Juventus.

But in terms of complete performances, the manner in which Brendan Rodgers' men overcame RB Leipzig on Tuesday night has to be up there with the best. It was a fast, aggressive and relentless display, showcased on European club football's grandest stage, on an evening where everything fell into place.

Nicolas Kuhn extended his fine form with two stunning goals. Reo Hatate dazzled with every pass and his uncanny vision. Arne Engels looked every bit the club's record-signing. And Callum McGregor put in one of his best, most industrious shifts in a green and white jersey to date.

Moreover, with two home wins from two so far – three in-a-row if you count last season's matchday six triumph against Feyenoord – Celtic Park has restored its long-absent swagger: deafening during the iconic operatic pre-match anthem, and literally rocking when Kuhn hit the net twice ahead of half-time, before Hatate pounced on a goalkeeping error in the second period.

Dare it be whispered… Parkhead might be a fortress once again.

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Of course, it could all come crashing down like the proverbial house of cards at the next asking.

I likened the entertainment value of Brendan Rodgers' side in the opening stretch of the current campaign to Martin O'Neill's golden era… and then Borussia Dortmund took seven off them on a night when dodging a cricket score genuinely felt like an achievement.

A well-earned stalemate against Atalanta in Bergamo went some ways towards putting that horrid result in the rear-view mirror. But this week's 3-1 triumph – against a side currently commanding second place in the German Bundesliga; having conceded just five goals with the league's best defensive record, no less – proved that the ship has been stabilised, no matter what seas lie ahead.

To this end, Club Brugge mark the next visitors to Glasgow's east end, followed by an away trip to Dinamo Zagreb. After that, Young Boys travel to Paradise towards the end of January, before an inevitably billed 'battle-of-Britain' showdown against Aston Villa comes into sharp focus.

It would seem three more points from a possible 12 would all but guarantee Celtic's place in the competition's play-off round, while a further nine could see them finish in the top eight, in turn automatically qualifying for the tournament's last 16.

The latter is, of course, the tallest of orders, even while buoyed by Tuesday night's heroics, but who'd have even considered the notion after 80 minutes at Signal Iduna Park five-and-a-bit weeks ago?

Club Brugge's unlikely 1-0 win over the previously flawless Villa on Wednesday evening proved nothing can be taken for granted in the Champions League, but Celtic supporters have surely earned the right to be confident at this moment in time.

Unbeaten domestically, top of the league, a handsome +15 goal difference advantage over second-place, through to a cup final this side of Christmas, and well within reach of tangible European progress.

It could even be argued that last point has already been achieved.

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For the avoidance of doubt, I'm far from a Pollyanna personality type. I err on the side of pessimism by default, and I’ve often wondered if there’s a glass on the table at all, far less one that may be half empty or full.

A child of the '90s, the decade-long scars inflicted by what felt like the interminable success of Celtic's city neighbours have barely healed – to the point where I preposterously view the Parkhead side as underdogs going into every derby a quarter of a century on.

But even I believe Celtic have earned the right to be confident in the here and now. And while I expect naysayers slinging woodwork insults from opposition fans, I can't fathom not enjoying the present on this side of the fence.

When else can we allow ourselves to be positive?

Celtic's Champions League campaign may well take a nosedive from here, but that doesn't detract from three-out-of-four top performances to this point, nor does it diminish the will of Celtic supporters who dare to dream.

Celtic have clinched more prestigious one-off results in Europe this century, but I'm of the view beating RB Leipzig was as significant as Gordon Strachan's 3-0 win over Benfica during the 2006/07 campaign – an occasion when, against the odds, the home side triumphed with a display of fast and aggressive football against a top opponent.

Indeed, Brendan Rodgers' side should now reach the Champions League play-off round. They might not finish in the top eight. They probably won't. But if they play anything like they did against Marco Rose's side, then they give themselves a fighting chance.

In any event, as was heard booming from the stands of Celtic Park on Tuesday night: don't worry, be happy.