Obviously the excellent Mr Atkinson couldn't possibly have given a penalty with the home fans understandably howling with outrage at how Alexis had just attacked the knee of one of their players with his back, and then cheated by lying on the ground as if in some pain.
As for the time that Coquelin (I think) headbutted the boot of one of their brave boys - well, he was lucky to stay on the pitch.
Same old Arsenal. Always cheating.