By Chris Harris
Per Mertesacker is bracing himself for his first appearance at Old Trafford - and the chance to face Robin van Persie.
The Germany defender spent one season as Van Persie's team-mate before the Dutchman left for Manchester United and he hopes that his training ground experiences will help him win that key individual battle on Saturday.
"He’s very skilful and has movement you don’t expect," Mertesacker told Arsenal Player.
"We trained a lot in the last year together. Sometimes you feel comfortable to play against him, sometimes not. He’s one of the players where he has to feel that you are there all the time and that’s what we as a team have to do on Saturday.
"In one way [training together helps], you expect his movement or you might anticipate his movement. He’s one of the players who can change his movements very quickly because he’s very skilful and has ability, we have seen it last year.
"But he’s not the only one who can score or be dangerous so it’s all about the team performance on Saturday.
"I’ve never played there before," added Mertesacker. "I think it’s a great experience to play against Manchester United at Old Trafford.
"My expectations are to face a world-class squad, or world-class 11 and to see our chances. That’s what we try to point out in the days before the match and to find our good game on Saturday. We need everybody on the pitch to put in a good performance."
Mertesacker has delivered a number of good performances already this season and he agrees with those who say he is playing the best football of his short Arsenal career.
"I think my first year was quite tough," he said. "You need to be patient here to settle down completely.
"This year I feel much more comfortable in my game and all around in the dressing room, with the language. That makes you feel more welcome, more recognised and it’s a better feeling.
"Everybody wants to take responsibility and wants to play. We have a very strong squad at the moment. When you get time to play, and feel good, and play better than last year, then you feel more confident to do everything."
Watch the full interview with Per on Arsenal Player.