Angel Di Maria and Edinson Cavani were among those to squander opportunities at the Parc des Princes, with visiting goalkeeper Laurent Pionnier producing a string of superb saves to keep his side in the contest.
The hosts remain 23 points clear at the top of the table but they failed to take full advantage of second-placed Monaco being held to a 2-2 draw by Caen on Friday.
And Blanc was quick to make his displeasure known.
"There is no reason to be satisfied with the result," he said. "There was room to win, but we were not effective offensively and I regret that there was no conviction in that area."
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With the second leg of their Champions League last-16 tie against Chelsea to come on Wednesday, Blanc did derive some comfort from the fact that his key men appeared to come through the game unscathed.
Di Maria returned from a thigh strain to complete an hour, while the likes of Zlatan Ibrahimovic, Thiago Motta, David Luiz and Javier Pastore all started on the bench.
"The essential thing, and what gives me the most pleasure, is that we did not pick up any injuries," he said.
"We decided to allow some to play and others to rest, and the end result was a satisfactory one."
PSG lead 2-1 heading into the second leg against Chelsea.