The World Cup winner was disappointed by his side's finishing at the Parc des Princes, arguing that two goals was just "not enough" given his side's dominance
The Parisians stretched their lead at the top of Ligue 1 to six points courtesy of second-half goals from Zlatan Ibrahimovic and Alex in a game that also saw Yohan Cabaye make his debut.
It meant PSG got back to winning ways after suffering a shock defeat in the Coupe de France against Montpellier before then dropping points against Guingamp, and although Blanc was satisfied with the win, he felt the margin of victory should have been greater.
"The victory is still essential but I am also interested individual and collective performances of the players," he told beIN Sports. "The result is very good considering it came after a disappointment at Guingamp and to win again at Parc des Princes is always a good thing.
"The only problem is that we failed to take all the opportunities we had in the first period, meaning the game became complicated.
"There is a lack of spontaneity, even if the players know and create opportunities to score goals. Given the number of chances that we had, two goals is good, but it is not enough."
Meanwhile, Blanc admitted his concern over the fitness of Edinson Cavani, who was replaced in the 76th minute by Ezequiel Lavezzi.
"It's a small muscle strain," the former France international was quoted as saying by RMC Sport. "We will be very attentive.
"By Saturday, we'll see what the medical staff have to say. He felt a pain behind his thigh."