Per Mertesacker, the Arsenal defender, has admitted that his side are still misfiring despite pulling off a dramatic late 2-1 win over Anderlecht on Tuesday night to remain on course for the Champions League knock-out stage.

The London side got away with a largely average display at the Constant Vanden Stock Stadium, with late goals from Kieran Gibbs and Lukas Podolski rescued all three points for the visitors.

Arsenal now have qualification for the knock-out stages back in their own hands ahead of next month's return tie against the Belgian club at the Emirates, before hosting Group D leaders Borussia Dortmund.

Mertesacker, though, is aware the Barclays Premier League team cannot afford the inconsistencies which have caused early-season promise to revert to familiar faltering displays and questions about the direction of Arsene Wenger's squad. Indeed, Arsenal have registered five wins from their opening 14 matches.

"Everyone knows that it was a difficult start for us and our confidence is not that much how we wanted it," the erstwhile Germany defender said. "The character is good, the mentality is good, but football-wise, we lack a few things. Our passing game is not as efficient as last year. We are not at our best. We have to admit that, be honest with ourselves and train harder."

By his own admission, Mertesacker has not produced the consistent form he showed last season, with the 6ft 7in German culpable for failing to deal with a cross which lead to Hull City taking the lead last Saturday.

The 30-year-old retired from international football after Germany's summer World Cup triumph but accepts the highs in Brazil came at a cost to his club performances of late.

"Personally it is difficult at the moment because that was really a long season last year," he added. "To come back from that World Cup and get the motivation back . . . I am nearly back, but you can feel there is something missing at the moment."