Les Bleus, who have dramatically improved since exiting Euro 2012 in the quarter-finals, are second in Group I with seven points from three games and trail Spain on goal difference.
Tuesday's clash against the world champions in Paris will not count for much, Deschamps said, if France cannot first beat Georgia at the Stade de France.
"In our qualifying campaign, if the match against Spain is to mean anything, we first need to win against Georgia," Deschamps told reporters.
"For the fans, it's as if the Georgia game had already been won. We are not going to say that Georgia are one of the best teams in Europe but they have good players and they are aggressive."
"Georgia defended very well against Spain. We could face the same situation," said Deschamps, referring to Spain's 1-0 win in Tbilisi in September, earned by a late Roberto Soldado goal.
"They will come to defend well. We will have to find opportunities to score. We will try to have a team who take control of the ball and creates problems."
"The risk of suspension is an extra danger," Deschamps admitted.
One option is to rest Koscielny and field Real Madrid's teenage defender Raphael Varane alongside Mamadou Sakho.
It will not solve, however, Karim Benzema's scoring problem.
"Singing La Marseillaise will not help me score a hat trick," Benzema told French radio RMC on Tuesday.
"The problem is that I haven't scored with France for a while."
