"Since the start of the season, I have said that staying up is our aim, and that clearly remains the extent of our ambition," Gourcuff told reporters after the game.
"This was a meeting of two teams fighting for survival. We need to face up to the reality if we are to turn things around.
"In terms of organisation and building the play, we did okay, even if we didn't create enough chances. But our commitment is not good enough. And commitment is not just physical, but mental too."
The result leaves Lorient in ninth place in Ligue 1 with 15 points from 11 games played.