The tifo at one end of the Parc des Princes was not a big blue-coloured Iceland flag, but a simple warning from PSG and their fans to their illustrious visitors, who were donning a peculiar ombre-mint outfit – together we are invincible. In football today, everything is content, but the message was obvious: this was not going to be another stroll for FC Barcelona.

Indeed, Sergio Busquets, Andre Gomes, with Lionel Messi failing to track back, and Andres Iniesta, Barcelona’s captain, drowned from the onset amid a scorching and scintillating pace imposed by PSG, as demanded by coach Unai Emery. This was not a host intent on shedding their tag of European parody and serial joke, of a parvenue from whom the shine was slowly fading; this was not even a PSG intent on revenge for their many continental implosions, in particular against nemesis Barcelona.

Just last week PSG were labouring, if not huffing and puffing, against Lille, relieved only by a fortuitous late strike from Lucas. So many familiar questions surfaced again: Could Edison Cavani truly replace Zlatan Ibrahimovic? Was Unai Emery the right coach for the club? Were PSG already a club in decline?

Barcelona being ‘Barca-ed’

Here was a PSG “Barça-ing” their opponents. They played out of the back, even when under pressure; they pressed very high, repeatedly troubling even Barcelona’s goalkeeper Marc Ter Stegen. PSG had a numerical superiority in the midfield, with Blasé Matuidi, off late unconvincing, but free-wheeling in his No. 10 role. Marco Verratti and Angel Di Maria moved the ball around slickly and with much precision. Thomas Meunier stifled Neymar and contributed plenty offensively.

Barcelona were vulnerable on the other flank as well, with Gomes often overran. He offered little protection to Sergio Roberto at left-back. In midfield Sergio Busquets was pedestrian; Ineista allowed for far too much space in behind his back. Cavani dropped back to tie up Busquests and force a gap between the Catalan lines. It was a tactic that worked.

Even when in possession in the latter stages of the first half, Barcelona were too predictable and too slow. Gerard Pique and Neymar delivered respectable performances, but, as a team, Barcelona were dross – with an unnerving apathy and indifferent attitude. The match was a surrealist undulation, with Barcelona schooled in footballing brilliance.

Emery and PSG were rewarded for all their attacking bravado. First, on 18 minutes, Samuel Umtiti clattered into Julian Draxler and Di Maria, the birthday boy, smashed the ball, a foot right of the D, through the Barcelona wall and into the net. Second, on 40 minutes, Messi dithered, lax and lethargic; Adrien Rabiot robbed him, Verratti picked out Draxler with a neat trough ball and the German fusilladed Ter Stegen.

‘Angel’ Di Maria

Third, Di Maria floated among angels again, with another splendid, curled strike. The goal epitomised PSG’s collective endeavour, reducing Barcelona to a set of cones. Trapp played it out from the back to Draxler, who waltzed past a half-hearted Leo Messi press and played the ball forward. Di Maria was not attacked as both Iniesta and Jordi Alba were ball-watching. He slammed in PSG’s third.

Cue Spanish bewilderment, cue a prolonged post-mortem of the death of Barcelona’s football, and cue the end of a great midfield, spearheaded by Andres Iniesta, and the imminent departure of coach Luis Enrique, but these 90 minutes were not about Barcelona’s perceived demise or crisis at the Camp Nou, but about PSG’s long-awaited ascent to, and acceptance by Europe’s big clubs.

This evening Emery’s appointment suddenly made sense. His hybrid formation metamorphosed into a master-navigator of a knockout competition, the Basque’s precise knack at Sevilla in the Europa League. Would PSG have played as good under Laurent Blanc and with Zlatan Ibrahimovic up front?

PSG maintained that impressive intensity, culminating in a fourth and tie-sealing goal from Cavani, whose night had so ominously begun with a heavy first touch in the box and a poor finish, almost affirming his status as choker. Instead, the Uruguayan was at the end of a regal mars from Meunier – or from Barcelona’s point view a meek amble over more than 50 meters, and after the Belgian had slipped the ball through Cavani, the latter finished clinically. Umtiti’s header against the woodwork became a mere footnote in night of utter superlative Parisian dominance from which Barcelona will not recover.