Wenger's ability to speak German also was decisive.
Asked if Ozil would get better under his new manager, his dad Mustafa said: "Of course, I do. Mesut is still not at his top level. I'm sure there is still 15 to 20 percent to get out of him and Mr Wenger will help him to do that.
"Arsenal is a very big club. The club tried hard to sign Mesut and he has a great perspective there," he said to Arsenal.com. "Mesut wants to help club to bring in some silverware. We appreciate the interest of such a big coach like Arsène Wenger.
Speaking about Wenger's influence, Mustafa said: "He was one of the deciding persons to convince us. It's also very helpful that he speaks German well.
"But that's not all. He also told us about his plans with the team and especially with Mesut. He wants him to play a big role in midfield."
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