Gourcuff, who had two mediocre seasons at Olympique Lyon, was included in a preliminary 26-man squad as the only proper playmaker but he failed to impress in a 3-2 friendly win over Iceland last Sunday, picking up a minor ankle injury in the process.
The squad was trimmed to 25 when striker Loic Remy was ruled out of Euro 2012 because of injury and Blanc on Tuesday had to drop two players before submitting his 23-man squad to UEFA.
"We had picked him because we wanted him to have an important role in the team," Blanc told a news conference at France's training camp in the sea resort of Le Touquet.
"Unfortunately, after five days, after the game [against Iceland], after another ankle injury, there were too many uncertainties surrounding him."
"He was behind [physically]. This injury is annoying but it's not just from the match, it's a recurrent injury," Blanc added. "There were to many uncertainties."
