After losing their first Premier League match to Aston Villa, the Gunners center back feels that a solid start against Fenerbahce is vital for the club's Champions League hopes.
"It is absolutely fantastic over there, so you have to be aware of the opening 20 minutes," he told Arsenal's official website. "You have to keep [the home fans] as quiet as possible, which is very hard.
The Gunners lost their first Premier League game of the season at home to Aston Villa on Saturday and, with injuries prevalent, are set to include four young rookies in their squad for the Champions League third qualifying round match.
The German defender feels that his side needs to quieten the infamously raucous Turkish crowd if it is to secure a good result.
"You have to play consistently over the whole 90 minutes and it is very important to be very focused on the first 15 to 20 minutes. We need to be ready and defend properly," Mertesacker explained.
"The first big target of the season is to qualify for the Champions League group stage. I know that it will be very, very tough - especially away from home.
"We need to go through with good form and be at our best. We want to show our fans at home that we are ready for the Champions League this season."