Brest defender Jonathan Zebina was shown a red card in second-half injury time as Caen and Brest played out a tense and unattractive goalless draw at Stade Michel d'Ornano.
In a game of very few chances, Thomas Heurtaux had the best opportunity to steal all three points but the Caen defender flicked a six-yard header past the post.
The visitors failed to work goalkeeper Alexis Thebaux once during the entire game and, in the dying moments, they lost talismanic Zebina, who was dismissed for a professional foul.
The result leaves Caen two points clear of the relegation zone, while Brest are only two points better off.