Giroud is yet to break his duck in three Arsenal appearances but his France team-mate Koscielny is confident in the striker's ability.
"I know Olivier, he is a good player but you know when a striker doesn't score mentally you ask some questions. When he scores the first goal, afterwards he will be more confident and easier for him to score," Koscielny told Arsenal Player.
"He has the quality to be strong with Arsenal, he works hard at training and when you have the opportunity to score and the ball goes 20 centimetres past the goal it is difficult.
"But he is a professional and will come back strong. One goal and after he will be OK."