Defending champions PSG stayed within touching distance of Monaco with a 4-0 rout of Guingamp at Parc des Princes in the French capital.
Edinson Cavani scored twice as PSG netted four unanswered goals in the second half to stay three points adrift of Monaco after 31 matches, with Nice a point further back, albeit having played an extra match.
Speaking afterwards, Emery told reporters: "At the break, we discussed to improve things, to exploit the spaces left by the opponent and to be more present next to goal.
"The first goal was the key. It made us gain confidence. In the second half, the team did the right thing.
"After the victories of Monaco and Nice, it was important to win."
Monaco and Nice were winners on Saturday and Friday respectively, but PSG kept up the pressure and ensured they remained second in the table thanks to Cavani, Angel Di Maria and Blaise Matuidi.
PSG laboured for almost an hour against Guingamp, until Di Maria opened the scoring in the 56th minute as substitute Javier Pastore made an immediate impact.
Cavani then scored twice in 10 minutes to take his league tally to 29 goals before Matuidi sealed the victory in stoppage time.
"It's always good for a striker to score, but the important thing is to win together and grow as a team," Cavani told Canal+.
"There are six more games left, one can win the championship, one continues to play and win.
"Monaco is another team, I'm talking about mine. We work hard. There are six matches left, that's a lot. One remains humble, with the title the objective."