The Premier League leaders face tests against the likes of Manchester City and Chelsea in December, but the center back remains confident of their ability to conquer those tests.
Arsene Wenger's side has been in superb form this season and tops the table with 35 points from 15 matches but will face a stern test of its title credentials in December, with Saturday's visit to Manchester City followed by a home fixture against Chelsea.
The Gunners will then take to the road for encounters against West Ham and Newcastle before the end of the year, but they have lost just twice in the league this season and the center back feels that they are in good shape after earning a 1-1 draw with Everton on Sunday.
"I think that was the toughest game we have been through the whole season," the Germany international told Arsenal's official website. "They pressured us high up, all the way through from the start until the end. We couldn't play that much and, in the second half, everything was possible on both sides, with chances here and there, so I think it was a fair result.
"We have tough games coming up over the next week and over the Christmas period. We just want to go one game at a time. We are really relaxed, we don't have to respond to anyone. We just have to do our job every single second of the game. That is our target, nothing else."