Arsenal full-back Bacary Sagna has admitted that his side may find it tough to overtake Schalke at the top of their Champions League group.

The German side shocked Arsenal with a 2-0 victory at the Emirates Stadium two weeks ago and Sagna believes that the Gunners must beat Schalke in the return match at the Veltins-Arena on Tuesday night.

Sagna said: "We are professional footballers and we want to finish first.

"We want to win the maximum amount of games. This is a big challenge now to be the best in the group.

"But as players we always want to be the best. It would mean we play against a team who finish second in their group."

The 29-year-old France international recently returned to action after suffering a broken leg.