Mustafi placed himself under the flight of the ball. Aguero ran 5 yards beyond the flight of the ball, then ran back and pushed Mustafi out of the way as he was about to head the ball clear.
I'm interested in what you think Mustafi should have done. Given the opportunity to stand and head the ball away, are you suggesting he should ignore the ball and follow Aguero?
He should have been well inside his own half with everything in front of him. Then he would have known where Aguero was and he would’ve been running on to the ball trying to header it instead of backpedaling from the halfway line. That also would’ve made it possible for him to do what Aguero did when they were both challenging for it. It was poor positioning that lead to the goal.
Well he was in the correct position to head the ball clear, which is his primary concern. Aguero took that position from him, not by going shoulder to shoulder or by challenging him for the ball, but by pushing him in the back. Have I been hallucinating, or something?