Open Extended ReactionsArsenal manager Mikel Arteta says Kai Havertz has undergone a "transformation in his body" while being injured and claimed he "destroyed all the metrics we had in the gym for the last 10 years." "There's been a transformation in his body," said Arteta. "Power, acceleration, muscle mass, the way that he has increased certain capacities in his body, his agility, he's been incredible. I was talking to the medical staff the other day and they were talking about that. 9, he will play as an attacking midfielder and he will be super important for us as a team."