A moment in the 38th minute of Paris Saint-Germain's recent 4-1 win over Amiens gave a glimpse of the attacking force that Thomas Tuchel's side might be about to unleash upon the European game in 2020.
As Angel Di Maria drove into the Amiens penalty area from PSG's left flank, Neymar, Kylian Mbappe and Mauro Icardi all surged towards the six-yard box. Di Maria's cross was blocked, but the sequence provided a foreboding snapshot of the firepower that the French champions now possess: at least €500 million worth of world-class attacking talent converging at speed upon an area the size of a large picnic rug.
And that's without even mentioning Edinson Cavani, the club's all-time record goalscorer, who has been left kicking his heels on the substitutes' bench. Rarely in the history of European football has a club been able to boast such a dense population of superstar forwards.
The sight of PSG's quatres fantastiques (Fantastic Four) simultaneously laying waste to the Amiens defence was all the more notable because barely three weeks previously, Tuchel had seemingly unambiguously declared such a four-man attack to be unworkable.
The four players spent half an hour on the pitch together in PSG's penultimate Champions League group-stage game away to Real Madrid in late November, after Tuchel sent Neymar on for Idrissa Gueye at half-time. But their lack of defensive work left PSG's central midfield pairing of Marquinhos and Marco Verratti dangerously exposed, and it was only once Icardi and Di Maria had been replaced by Pablo Sarabia and Julian Draxler that the visitors succeeded in clawing back a two-goal deficit to secure a 2-2 draw.
"You should ask Marquinhos and Marco Verratti, I think. They don't find it very enjoyable to run around in a midfield two," Tuchel commented later that week.
"For me, it's not balanced enough at this level. I think it's absolutely necessary for us to play with three midfielders. ... I really get the impression that everyone thinks it's normal to play with four forwards. I'm convinced that it's not possible. We play against very balanced, very strong teams. If you ask the defensive players, they'll tell you the same thing."
With hindsight, it is now apparent that rather than an unequivocal dismissal of the system, Tuchel's words were intended as a warning to his four star attackers that if they wanted to play together, they would need to put in the requisite defensive effort. Because in the games that led up to Ligue 1's midseason break, he gave them a succession of opportunities to prove to him the system could work.
It has been a case of evolution rather than revolution. During the second half in both the 2-2 draw at the Bernabeu and the 2-0 win at home to Nantes that followed it, Tuchel subtly adjusted PSG's shape from a 4-3-3 formation to a 4-2-3-1.
Three days after the Nantes game, he tested out an attacking 4-4-2 formation from the start in a 3-1 win at Montpellier, with Neymar lining up wide on the left, Sarabia filling in for Di Maria on the opposite flank and Icardi partnering Mbappe through the middle.
The same attacking quartet started in PSG's final Champions League group game, a 5-0 romp at home to Galatasaray, before Di Maria returned from a muscular injury to take over from Sarabia.
With Neymar, Mbappe, Icardi and Di Maria in tandem from kick-off for the first time, PSG won 4-0 at Saint-Etienne and then ran in another four goals against Amiens, which left them seven points clear at the Ligue 1 summit with a game in hand.
Including a 4-1 win over second-tier Le Mans in the Coupe de la Ligue, for which Neymar was rested and Icardi started on the bench, PSG have scored 20 goals in the five matches they have played since Tuchel introduced his attacking 4-4-2 configuration.
Both Mbappe (seven goals, five assists) and Neymar (four goals, six assists) are in double figures for goal contributions over that period, while Icardi has scored four goals and laid on one more, and Di Maria has scored one and made two. PSG racking up armfuls of goals in domestic fixtures is of course nothing new, but this is the first time since Tuchel joined the club in 2018 that they have managed to string together a succession of victories with such a top-heavy attack.
While the system inevitably puts a strain on PSG's central midfield pairing, that burden has been eased by the defensive application demonstrated by the front four. Neymar, in particular, has upped his work rate noticeably and drew admiring words from Tuchel after harrying and closing down for the entire 90 minutes of the win against Amiens.
"If we want to play with four attacking players, everyone has to be ready to defend," the PSG coach said after the victory over Saint-Etienne. "We're coming off three extraordinary matches with players who are making an effort."
From an attacking perspective, the system has the twin benefits of allowing Mbappe to play up front with a classic, line-leading partner, as he did in his breakthrough season at Monaco with Radamel Falcao, and enabling him to combine regularly with Neymar on the left flank.
The pair, who have become close friends off the pitch, noticeably exchange more passes than any of PSG's other attacking players and in December alone, Neymar set up five goals for his French team-mate.
The viability of the current tactical approach has been enhanced by the improved form of central midfielder Leandro Paredes, who has belatedly started to show why PSG were prepared to pay €40 million (potentially rising to €47m) to sign him from Zenit Saint Petersburg a year ago. Seemingly more at ease in a midfield two than a three, the Argentina international has started four of PSG's last five games. His upturn in form additionally offers Tuchel the possibility of restoring Marquinhos to his preferred role at centre-back.
Tuchel's initial preference this season was to play in a 4-3-3 formation, but the system obliges him to omit one of his four star attackers and to rely on central midfielders who are not exactly renowned for their creativity. Marquinhos, Verratti and Gueye may have shone in PSG's 3-0 demolition of Real Madrid at Parc des Princes in September, but they have scored only two goals between themselves all season.
In truth, Tuchel has been trying to squeeze four attacking players into his starting XI ever since he arrived in Paris 18 months ago. The forward line he inherited from Unai Emery was commonly referred to as "MCN" in the French media, in reference to Mbappe, Cavani and Neymar, but Tuchel repeatedly made it clear that he considered Di Maria to be just as integral to his plans as the other three big-name attackers at his disposal.
He appeared to have struck upon a winning formula in November 2018 when a hard-working PSG side including Neymar, Mbappe, Cavani and Di Maria, and featuring Marquinhos in a hybrid central midfield/centre-back role, defeated eventual Champions League winners Liverpool 2-1 in a group-stage game at Parc des Princes.
But injuries to Neymar and Cavani prevented him from redeploying the system against Manchester United in the competition's round of 16, when Tuchel's men crashed to a humiliating away-goals defeat after winning the first leg 2-0 at Old Trafford. The last time Neymar, Mbappe, Cavani and Di Maria lined up together at kick-off was for a home game against Guingamp in January 2019. PSG won 9-0.
The one not inconsiderable caveat regarding PSG's ultra-attacking strategy is that it has not, as yet, been tested against elite opposition, which has prompted calls for caution.
"I never had any doubts that the four of them could play together at the same time, especially when the opposition are called Saint-Etienne or Amiens," influential Canal+ pundit Pierre Menes said recently. "Before calling them 'the Fantastic Four,' I'd perhaps wait to see them against more robust opposition."
Tuchel will have league games against Monaco, Lille and Lyon in which to test the formula further, should he decide to, before PSG face off against his former club Borussia Dortmund in the first leg of their Champions League last-16 tie at Signal Iduna Park on February 18.
In Marco Reus, Jadon Sancho, Thorgan Hazard and new signing Erling Haaland, Dortmund boast an attacking roster that is jam-packed with talent. If Tuchel decides to fight fire with fire, things could get very hot indeed.