Per Mertesacker's transformation from Arsenal misfit to cult hero set to land defender a contract extension "I'm very delighted here with the club, especially after the first year was tough for me, a very tough challenge," said Mertesacker. The boss always trusted me in a special way so I think it's a little reward that we talk a bit on things. There's no rush but it seems to be that some guys are delighted with my performance at the moment. I'm pleased with the situation. Mertesacker came under heavy criticism for his performances during his first season in England but says that the faith of Arsenal manager Arsène Wenger was pivotal to his adaptation to Premier League football. His existing deal expires at the end of the 2014-15 season and, well aware that his form has alerted other European clubs, Arsenal want to get a new contract in place as soon as possible. "The manager always trusted me," said Mertesacker. I went through a lot of mistakes maybe at the beginning but he always said, 'you will go through that because you are intelligent and a good player'. Mertesacker's cult status has further grown this month after he agreed to promote a new line of T-shirts in his honour that were produced by fans and carry the message (Big F****** German) on the front. "That was not my own idea," he said. I'm very delighted they gave me a lot of time to settle in, to adapt to that level and now I try to give something back. Mertesacker is also adamant that there is much more to come from his Germany team-mate, Mesut Özil, who missed a penalty in Tuesday's 2-0 win against Marseille. "He has made good progress I think," said Mertesacker. He's in good form - he was always a threat in every second. He never gave up, despite the penalty that he missed. I think we're delighted with him, especially the transition from defence to offence. He's always a threat, he can play the ball, he's the one who goes deep all the time. He's in good form and I think we will see more. He gets himself into good positions so the goals will come for sure. Mertesacker also believes that the presence of Özil, who provided the assist for Jack Wilshere's second goal on Tuesday, is creating space for his team-mates. "He moves well between the lines, so it's always difficult to defend against him," he said. When the centre back comes out with him there's always space for others to go into. I think overall he's the member of our team who helps us to create more chances to make the opposition more vulnerable.