The 2007 world champion qualified in 10th spot, some half a second off the pace of team-mate Fernando Alonso, and endured a troubled race that included a spin and brake issues.
"It was a difficult race," admitted Raikkonen, who was making his landmark 200th grand prix start at the Canadian venue.
"We were stuck behind people and had some brake issues in the beginning. Then I spun. The same happened in practice one. For some reason we seemed to get a kick suddenly [from the engine] and I spun.
"Every time I came out of a pitstop there always seemed to be people in front of me. In the end the car felt a bit better and was fast. But it was just difficult."
His team-mate Alonso had a better day by comparison, but was blunt when asked if Ferrari had been fortuitous.
"We got some lucky extra points with the DNFs at the end," Alonso confirmed to reporters after the race. "Without the DNFs our positions were probably ninth and 14th."
Alonso currently sits fourth in the drivers' standings on 69 points, while Raikkonen is 12th on 18. Ferrari are third in the constructors' championship but find themselves well behind leaders Mercedes and Red Bull, with fourth-paced Force India just 10 points in arrears.