Monaco handed French champions Paris St Germain their first home defeat of the Ligue 1 season with a 3-1 away victory at the Parc des Princes on Friday that opened up the championship race.
Maghnes Akliouche had Monaco ahead at halftime, and Aleksandr Golovin and Folarin Balogun netted after the break for the visitors, while Bradley Barcola scored a consolation for PSG, still four points clear of second-placed Racing Lens in the standings.
Lens, however, have a chance to cut into the lead when they host bottom-placed Metz on Sunday.
Monaco, who PSG had eliminated in the Champions League last month, moved up to fifth with 40 points, still 17 behind the leaders.
PSG will have to pick themselves up as they host Chelsea on Wednesday as they continue their defence of the Champions League title.
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