Edinson Cavani's late penalty earned Paris St Germain a 1-0 home win against Nancy as the French champions put pressure on Ligue 1 rivals Monaco on Saturday.
Uruguay striker Cavani netted his 27th goal in 26 league appearances this season to put PSG on 62 points, behind Monaco, who host Nantes on Sunday, on goal difference.
Nice are third, also on 62 points, after Wylan Ciprien's 69th-minute goal gave the Azureans a 1-0 victory at Dijon.
PSG, who were held to a goalless draw by Toulouse at the Parc des Princes two weeks ago, struggled again on their turf but eventually wore out a brave Nancy side.
"The essential is here, we won. It is not always easy to play against these teams at home," said midfielder Blaise Matuidi.
Coach Unai Emery surprisingly handed a start to Goncalo Guedes with Julian Draxler on the bench, a decision that left the home side lacking speed up front.
However, with 10 minutes left, fullback Serge Aurier was brought down in the box and Cavani converted the resulting penalty with a powerful low shot.
Nancy are 17th on 28 points, one point above the relegation zone.