'We were at 10 per cent less because we thought we were through' - Per Mertesacker

Arsenal defender Per Mertesacker believes complacency played a part in the Gunners' 2-0 Champions League defeat at Napoli but the German is happy to be in the draw for the first knockout stage.

The Londoners secured their place in the last 16 with victory over Marseille last time out and seemed a little under par at the Stadio San Paolo, where goals from Gonzalo Higuain and Jose Maria Callejon earned Napoli all three points.

A poor night for Arsenal also saw midfielder Mikel Arteta pick up a red card midway through the second half.

The last-16 draw is made on Monday and Mertesacker told Sky Sports News: "We were at 10 per cent less mentally because we were always thinking we were through.

"But we deserved (to go through) because we played a good group stage. We're second in the group for the draw next week."