Per Mertesacker says Arsenal have the perfect chance to prove how good they are by winning at Chelsea on Sunday.

The Gunners won 5-3 at Stamford Bridge last year in a sensational game that Arsène Wenger admits helped to “turn our season”.

Mertesacker is wary of the threat posed by Rafa Benitez’s side, but feels Arsenal have the quality to claim another important three points in west London.

“We showed last season that we can win there,” the Germany defender said. “We have to be confident, that is the most important thing.

If you want to be in the top four, you have to compete with Chelsea, Manchester City, Manchester United and Tottenham

“When we put our opponent under pressure we are always dangerous. That must be our target at Chelsea as well.

“If you want to be in the top four, you have to compete with Chelsea, Manchester City, Manchester United and Tottenham. Those teams are all in the [same] zone as us, so we need to win against those four as much as we can.

“This is a good chance to show how good we are. We need to show our character, that is the most important thing.”

Arsenal will come up against the in-form Demba Ba at Stamford Bridge, and Mertesacker accepts keeping him quiet will be a difficult task.

“I saw him against us at the Emirates [when he was playing for Newcastle] and he did well,” he said. “He is a very compact player, physically strong and quick too.

“But with this Chelsea team, we can't focus just on one player. He can be a threat, but we have to take care of our own defensive game. That is the first thing.”

Copyright 2014 The Arsenal Football Club plc. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source Rob Kelly 17 Jan 2013