Ahead of the second leg of Barcelona's Champions League quarter-final with Paris Saint-Germain, Blaugrana boss Xavi promised "a footballing war" on Tuesday. What he didn't account for, though, was just how much of a role he and his own team would play in their own downfall.

The soon-to-depart coach lost his head as madness unfolded before him at the Olympic Stadium, with mistakes from Ronald Araujo and Joao Cancelo - combined with clinical finishing from Kylian Mbappe - meaning Barca blew the aggregate lead they had built up from the first leg, and which they soon added to thanks to Raphinha's third goal of the tie.

Araujo's moment of madness, however, changed the coiurse of Barca's European adventure. Just under 30 minutes in, the Uruguayan defender dragged down Bradley Barcola as he ran through on goal, leaving the referee with no choice but to send him off.

The Parisians, predictably, capitalised, piling on the pressure as Luis Enrique switched his system to allow his side to pour forward. In the end, it was Ousmane Dembele who took advantage, finishing a well-crafted move with an emphatic effort into the roof of the net. The visitors then completed their turnaround after the break, as Vitinha levelled the tie with a guided strike from outside the box before Kylian Mbappe converted from the spot either side of Xavi losing his head and seeing red himself.

Mbappe rounded out the scoring shortly before the full-time whistle, reaping the benefits of another Blaugrana blunder - this time a poor clearance from Jules Kounde - to smash home with from close-range.

By the end of it all, Xavi's footballing war had ended in defeat, as PSG's players celebrated banishing the ghost of La Remontada. Barca, meanwhile, were left to rue their mistakes and wonder what might have been if they had simply kept their heads on the night.

GOAL breaks down the biggest winners & losers from the Olympic Stadium...

WINNER: Kylian Mbappe

Mbappe may be on his way out of PSG, but he has always maintained his promise to do everything he can to bring European glory to the French capital. Thus far, though, his mission has been a tale of failure after failure, most of which have not reflected well on the World Cup winner. However, this season - his last at Parc des Princes - might just prove to be his best shot at ending the misery.

After an underwhelming first-leg performance, Mbappe was again quiet for long periods on Tuesday, as he was locked down by Kounde and Pau Cubarsi. However, in the end, Mbappe proved decisive in the big moments. He converted from the penalty spot to give PSG the lead on aggregate, and was clinical from inside the six-yard box to score the goal that put the tie to bed for good.

Mbappe could barely have asked for a more favourable opponent than Borussia Dortmund in the semi-finals, meaning a place in the final at Wembley on June 1 is well within reach. Whichever team comes out of the other side of the bracket will undoubtedly be favoured in that final, but Mbappe's hopes of a perfect parting gift are suddenly within touching distance.

LOSER: Ronald Araujo

What were you thinking, Ronald?! The Uruguayan was one of the best defenders in Europe last season, a reliable source of quality at the back as the Blaugrana eased to a La Liga title. He hasn't quite been the same this campaign, though, as injuries and poor performances have marred his season.

On Tuesday, though, he made his most high-profile and costly blunder. He chose to engage Barcola as he ran through on goal, clearly fouling the winger narrowly outside the box. Araujo protested, arguing that fellow centre-back Cubarsi could have slid across to deny the PSG forward a shot on goal, but his complaints rightly fell on deaf ears.

It proved to be the turning point of the whole tie, as Barca were forced to sit back and defend their lead, while PSG were given space to play the devastating football they are capable of. The visitors got the job done, and with La Liga pretty much out of reach, Araujo's poor decision now has Barca facing a trophy-less campaign.

WINNER: Ousmane Dembele

There were grim scenes outside the stadium for Dembele to endure before kick-off. Videos of Barca fans burning his shirts and chanting expletives were widely circulated on social media, and inside the ground, jeers rained down every time the former Blaugrana winger touched the ball.

To his credit, the France winger steadily went about silencing the home crowd, even if he made a couple of sloppy errors early on. He bagged the Parisians' first goal on the night as they embarked on a dramatic comeback, and won the penalty that sealed the third.

Dembele was perhaps treated unfairly during his time at Camp Nou, a target of fans, the club and media alike as they looked for a scapegoat. This, then, was the perfect revenge performance on his return to his former club.

LOSER: Joao Cancelo

Another stinker from a Barcelona defender. Cancelo's loan spell has been mixed at best, with the Portuguese providing some moments of magic going forward while also looking vulnerable going in the other direction. On Tuesday, he came up short when it came to his defensive responsibilities.

Cancelo put in a brainless sliding challenge on Dembele, gifting the Parisians an easy chance to take the lead in the tie. Mbappe was never going to miss from the spot, making Cancelo look a fool for a costly moment that capped a proper collapse from the home side.

With Alejandro Balde set to return from injury next season, questions will be asked as to whether Cancelo's loan from Manchester City should be made permanent. His performance here was certainly a mark against keeping him around.

WINNER: Luis Enrique

Is this what vindication looks like? Luis Enrique oversaw a vast re-tooling of this PSG squad last summer, bringing in a dozen new faces while clearing some expensive older heads off the books. He has certainly had his detractors since doing so - especially given the authoritarian way he has managed the disgruntled Mbappe.

But here, all of his methods were proved right. This was a showing in the mould of what the manager must have had in mind, with the Parisians playing in a vertical, direct and exciting manner. His selections were questioned in the first leg, but his decision to start youngster Barcola over the experienced Marco Asensio proved a masterstroke, as it was the ex-Lyon talent whose run in behind led to the tie-changing moment of Araujo's red card.

PSG may have been gifted a man-advantage, but they still had to make the most of it, and entirely dominated the fixture for the last hour. 'La Remontada' will remain iconic, but this wasn't a bad comeback, either. One thing that can't be debated, however, is that Luis Enrique has come out on top both times.

LOSER: Xavi

Barca have been much better since Xavi announced his intent to leave in January, looking a far more composed side with the knowledge that their coach is soon to depart. And Xavi has been part of the reason for that, cutting a more relaxed and freed presence on the sidelines.

Here, though, he was anything but. The former midfielder wasn't helped by his team, of course, who were erratic on the night, but Xavi set a poor example himself, kicking out at a camera stand in protest at a refereeing decision early in the second half that led to his dismissal.

And so, despite Barca's best efforts, it seems Xavi's Barca tenure will end with a whimper. A run to the Champions League final might have convinced him to change his mind, but with a quarter-final exit sealed, and league glory all-but gone, Xavi's farewell tour looks set to be a low-key affair.