Paris Saint-Germain needed a late penalty from top scorer Edinson Cavani to scrape home against struggling Nancy 1-0 in Ligue 1 on Saturday.
PSG moved level with leaders Monaco, who have a vastly superior goal difference and can restore their three-point lead against Nantes on Sunday.
It was a poor performance from PSG, who seemed to be heading for a second consecutive home draw when right-back Serge Aurier won a penalty and Cavani tucked it away with 10 minutes left. Video replays suggested Aurier went to ground too easily, although at full speed it would have been hard to tell.
Cavani's penalty was almost saved by goalkeeper Sergey Chernik, who stood up until the last moment and guessed the right way.
Just before the goal, Nancy came close to scoring when substitute Alexis Busin's shot hit the left post and rolled onto the opposite upright.
It was a lucky reprieve for a PSG side playing with none of the flair and panache they showed when winning 5-1 at Marseille on Sunday.
That was also because of Nancy's resolute and organised defending, much in the same way as Toulouse when they drew 0-0 at the Parc des Princes two weeks ago.
"It's difficult to play well against teams that deny you space," Cavani said. "If you don't score early on in these games, these teams become more confident."
Cavani's goal was his 27th in the league, but otherwise he played poorly, heading wide from point-blank range early in the second half after rolling a shot wide in the first.
With a return match at Barcelona in the Champions League on Wednesday, PSG coach Unai Emery rested winger Julian Draxler and midfielder Blaise Matuidi.