Per Mertesacker is delighted with the way he has adapted to life in the Premier League during his first season in England. The Germany international moved to Arsenal at the end of last summer\'s transfer window and proved to be a calm presence at the heart of the Gunners\' defence. As he recovers from an ankle injury that has sidelined him since February, the 27-year-old admits that the initial transition was difficult. \"Sometimes I felt like it was very hard, especially when I first came here,\" Mertesacker told Arsenal Player. \"It was tough to settle down [and I was] very quickly into the first squad. There was sometimes a lack of performance but I think you have to go through that to improve yourself. \"I am very comfortable here now, and very proud to be with this Club.\" Mertesacker says he has enjoyed the challenge of moving from the Bundesliga to test himself in the Premier League. \"In general you are playing the best players in the world,\" he said. \"You always have to perform at a high level. \"It is at a constant level and that is what makes the Premier League so good and so sharp.\"