Flick's tactical approach, featuring an extremely high defensive line, also seemed ripe for Mbappe and Vinicius to pillage with their pace.
Swedish prosecutors on Tuesday confirmed an investigation had been launched -- without naming Mbappe -- following an alleged rape at a plush Stockholm hotel on October 10.
Los Blancos take on their rivals without the French forward, ruled out for three weeks with a hamstring injury.
The format may be new, but few would bet against the winner staying the same.
The 2018 World Cup winner almost joined Caen as a teenager before eventually signing for Monaco.
The France captain, to his credit, was sublime in creating the goal that beat Austria 1-0, but his failure to score at a Euros will weigh heavily on a player who has found the net 12 times at World Cups, including a hat-trick in the 2022 final.
"The Euros is very important in our careers, but we are citizens first and foremost and I don't think we can be disconnected from the world around us," said Mbappe.
Mbappe, 25, verbally agreed to move to Real in February and then announced in May he would leave PSG at the end of the season.
PSG's decision to withhold Mbappe's salary is related to an agreement between the two parties made last year, at the start of the season, when the player accepted to waive part of a bonus due to him, the source said.
Revel's young supporters had implored Mbappe to make the trip to the game played at Castres - Revel's humble stadium only has capacity for 2,000 fans in the Haute-Garonne south-western region - in a video posted on social media.
Barcelona forked out fees in excess of 100 million euros ($109.24 million) for Philippe Coutinho, Antoine Griezmann and Ousmane Dembele between 2017-19, but the club's financial issues mean they are unlikely to splurge on big new signings anytime soon.
Arsenal's search for a proven goalscorer to spearhead their challenge for a first Premier League title since 2004 could also loom large.
"We are not a couple but that is mainly because he doesn't want us to be," the Spaniard joked.
The prestigious award has been dominated over the last 15 years by Messi and his old adversary Cristiano Ronaldo, who have won it 12 times between them.
PSG were eager to bounce back from their 4-1 defeat away to Newcastle United three weeks ago and they ultimately had too much attacking quality for their Italian visitors at the Parc des Princes.
"Throughout the match they were fresher than us," said Luis Enrique after his first loss as PSG coach.
Messi, who recently left Paris Saint-Germain for Inter Miami, is in with a chance of succeeding Karim Benzema and winning the Ballon d'Or for the eighth time in his remarkable career after leading Argentina to World Cup glory in Qatar last year
Ancelotti added that Real are unlikely to do any more transfer business in the current window which closes on Sept. 1.
Mbappe came off the bench to bury a spot-kick he earned just past the hour mark, but Toulouse equalised with a penalty of their own via Zakaria Aboukhlal four minutes from the end
