Per Mertesacker admits there were serious doubts inside the Arsenal locker room after the first game of the season.
The German revealed the mood going into 2014 is in stark contrast to the pessimism following the opening day defeat by Aston Villa.
He said: "When we lost that first game, everyone was in a bad mood but we have turned things around completely and are delighted.
"We've had a great first half of the season and the aim now is to stay where we are. But we are contenders. That is all. We have not won anything yet."
