PSG are currently nine points clear at the top of their domestic table and well on course to reclaim the crown they let slip to Monaco last season with their squad bolstered by the summer arrivals of Neymar from Barcelona for a €222 million fee and Mbappe, in a deal that sources told ESPN FC was worth €180m.

Their Champions League campaign had been plain sailing until Tuesday night's 3-1 defeat at Bayern Munich that led the club's CEO and chairman, Nasser Al Khelaifi, to order Unai Emery's men to "wake up now."

Al Khelaifi, who saw PSG's unbeaten record in all competitions come to an unexpected halt at Strasbourg last weekend, was at the heart of the club's massive summer spending spree which was sharply focused on bringing European success to the French capital.

Le Graet told RMC that the club's owners, Qatar Sports Investments, might regret spending so much if their only return this season is domestic trophies.

"PSG have great players and I'm convinced that it's a lesson they will learn well," he said. "We need PSG. I have often said it as a joke, but if PSG signed those players to be French champions, it's stupid.

"You don't need to spend so much money to win the French title. But, at the end of the day, they have still finished top of their group."