Arsenal defender Per Mertesacker has insisted that his side cannot afford to lose their Champions League home game against Montpellier on Wednesday.

The Gunners are currently second in Group B with seven points from four matches, a point behind leaders Schalke.

"There is no space for weak games or for another home defeat," BBC Sport quotes the German as saying.

"We are completely concentrated on this game and we have to take this stage as Arsenal have done in [previous] years.

"The group is still open for the teams, and we have to show we can go through and make clear that Arsenal will go to the next round."

Montpellier are at the foot of the group with just one point from four games.