The 34-year-old also admitted that at times Ozil’s laid-back attitude would leave him “really p**sed” with the midfielder for days and weeks.
“First of all Ozil loves playing football. It doesn’t come across so often,” Mertesacker was quoted by Mirror UK as saying ahead of Arsenal’s Premier League clash against Watford on Sunday.
“He is a genius in terms of what he can produce with the ball, you can see that in every training session.
“Once he gets the ball, he’s rested. He thinks he is playing in the park. He can deliver the ball that no one else can deliver. He has got that magical sense.
“But he is not the kind of guy who approaches people and says, ‘You need to do this, that and that’.
“He’s a different character and sometimes I struggled with that. Sometimes I was really p**sed with him for days and weeks.
“But he delivered magic moments for us, moments when you thought he could go to another level.”
Ozil has struggled for starts since Unai Emery replaced Arsene Wenger as Arsenal manager.