The Gunners sit fourth in the table for the first time this campaign after their 1-0 win over QPR on Saturday saw them overtake Chelsea, who lost 3-1 at home to Aston Villa.
With home matches against four of their main rivals for a place in next season’s Champions League still to come, Koscielny says their fate is in their own hands.
“It was very important to win [against QPR], because we drew against Wolves and we wanted to win this game and we did,” Koscielny told Arsenal Player.
“It is good for us that we are fourth, so we need to stay in fourth spot and maybe even get to third. We work every day to get stronger.
“We know we [still have to] play at home against Chelsea, Manchester United, Manchester City and Tottenham, so we have the cards in our hands. We can go higher in the table [if we win at home].”
Arsenal face Fulham at Craven Cottage on Monday evening and could go level on points with third-placed Tottenham, who play West Brom on Tuesday.