The defending champions have made a perfect start to the season, but that will be tested by fellow unbeaten side Marseille, who have recruited well over the summer.
Marseille and Monaco set to fight it out who is best placed to take the fight to Paris Saint-Germain and Neymar
In the top storey of Ligue 1, something has to give.
That is besides the expectation that every other club must give way to the Paris Saint-Germain juggernaut sooner or later – probably sooner.
There is still intrigue over who can best keep up the chase of the club from the capital. This weekend may give us a strong clue.
Something has to give at the Stade Louis II, home of the champions Monaco, who have weathered a tricky summer off the pitch, with the departures of a number of players and the extended negotiations over the future the wantaway teenager Kylian Mbappe.
Monaco, even without Bernardo Silva and Tiemoue Bakayoko – both lured to the Premier League – have kept up their championship form so far.
Victory last weekend, their third of the season, set a new record, of 15 Ligue 1 triumphs on the trot.
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Meanwhile, along the Mediterranean, Marseille, in drawing 1-1 with Angers notched up a 13th consecutive match in the top flight without defeat.
Not a cause of vast celebration, perhaps, but an important touchstone for a club given to erratic mood swings and yearning for a period of stability and progress.
Marseille, who qualified for the group stages of the Europa League on Thursday, know that Sunday’s trip along the coast to Monaco represents an real, tough examination of where they now stand in France’s hierarchy.
It is not yet a year since Marseille came under the ownership of Frank McCourt, the American billionaire who once had the LA Dodgers, the baseball club, in his portfolio.
McCourt recognised the potential in the club’s vast fan-base, its traditions – no other French club has ever won a European Cup, as Marseille did in 1993 – and that in the era of a mega-rich PSG, Ligue 1 was gaining status.
McCourt did not, and cannot, give Marseille the same financial superpowers that PSG have enjoyed under their Qatari patrons, but he might propel the club to second-best in Ligue 1.
In the two transfer windows in which the new owner has had an influence so far, Marseille have recruited a calibre of player that had been beyond their reach.
A club record fee, €30 million (Dh131.3m), was paid to West Ham United for Dmitri Payet in January, a considerable sum given that Payet turned 30 two months later.
Patrice Evra, the veteran left-back, joined at the same time from Juventus. Both had represented France, all the way to the final, at Euro 2016.
This summer, Marseille have gone for players of similar pedigree: not men who might feature on the wish-lists of the high-rollers in Paris, but worldly campaigners such as Adil Rami, the experienced France central defender from Sevilla, and Luiz Gustavo, the Brazilian midfielder, formerly of Bayern Munich, signed from Wolfsburg.
They also repatriated their former captain and France international goalkeeper Steve Mandanda after his unfulfilling season at Crystal Palace and they hired Valere Germain, the striker, from Monaco, where he had made significant contributions, as a foil to Monaco’s leader of the line Radamel Falcao, to winning the title in May.
Those new arrivals have come in at a total of less than €35m combined.
Appetites whetted by the idea of some economic good health after years of boom-and-bust, supporters of Marseille are keen to see, before the transfer window closes, a new, lean goalscorer to add to the solid spine of players now at head coach Rudi Garcia’s disposal, not least because striker Clinton Njie, the scorer of three of their five goals in the league so far, is out injured for two weeks.
Garcia, the former Roma head coach who joined Marseille as McCourt completed his takeover last October, is pleased at the unbeaten record that, in domestic football, goes back to March 1.
“These statistics don’t count for too much,” he said. “But they can be useful motivation to players when they are struggling in a game.”
And struggling is what Marseille were for the two Ligue 1 encounters against Monaco last season. They lost 4-0 and 4-1 in a fixture that has the status and the edginess of a local derby, even if a long stretch of coastline separates Monte Carlo from the great port of France’s south, not to mention a vast cultural divide.
The tough, gritty city from where Marseille draw their vibrant support on the one hand; the magnet for millionaires that is the small Principality of Monaco.
Marseille’s last visit there was their last defeat, a 4-3 back-and-forth of a French Cup tie that went into extra time.
More drama of that sort on Sunday and Ligue 1 will go into next week’s international recess well satisfied.