Monaco crushed Sedan 3-0 to seize top spot in a tight Mediterranean-dominated French first division on Saturday.
The principality team lead the top flight only on goal difference, however, as they and neighbours Nice and third-placed Olympique Marseille, who play on Sunday, are all equal on 42 points.
Monaco, who could be overtaken by Marseille should the former European champions bring at least one point back from their trip to Bordeaux on Sunday, have been rewarded for their consistency since the beginning of the year.
The win owed much to midfielder Jerome Rothen, who forced Sedan defender Johann Charpenet to score an own goal in the 34th minute before setting up Sebastien Squillaci for a second five minutes later.
Croatia's Dado Prso sealed victory with a last gasp goal four minutes from time and, with 42 points, Monaco are now assured of avoiding relegation.
The team coached by former France captain Didier Deschamps have been unbeaten in their last nine games.
"Tonight, like Nice, we made sure we would remain in the first division next season," Deschamps said.
"We're leaders for sure but Marseille play tomorrow. The most important thing for us was to confirm our victory in Nantes last week.
"It's important to show consistency ahead of a showdown against (reigning champions) Lyon. We will have no time to celebrate," Deschamps added.
Monaco host Lyon on Tuesday for a game which could turn out to be decisive.
LYON HELD
Nice remained in the title race thanks to their 1-0 victory over En Avant Guingamp, defender Noe Pamarot scoring his first goal of the season for the Riviera team.
Champions Olympique Lyon, who were also in a position to claim top spot, had to be content with a goalless draw at home against ten-man Nantes and slip to fourth.
The defending champions again squandered two crucial points against Nantes, who lost Eric Djemba-Djemba after the defender was dismissed following a second yellow card on 42 minutes.
Lyon even missed a penalty when Brazilian Juninho Pernambucano's attempt was stopped by Nantes goalkeeper and captain Mickael Landreau.
AJ Auxerre, who have a game in hand, easily dismissed Sochaux 2-0 under heavy snow, their magic pair of Djibril Cisse and Philippe Mexes scoring in the 34th and 54th minutes.
The Burgundy team could also seize the lead should they beat Sedan in the replay of a game cancelled earlier in the season because of a refereeing error.
Paris St Germain snatched a lucky 1-0 win away at Racing Strasbourg and are clinging to the leading group.