To be honest that sketchy angled replay was inconclusive and it looked ball to hand rather than hand to ball... maybe its my rose tinted specs?
It was a stupid mistake for such an experienced defender. Regardless of ball to hand (Though I think he just lost his head for a moment), he dipped his body down slightly in order to do that. Poor judgement, especially after Arsenal just scored, worst time to get sloppy. Could of changed everything, as it stands it's just going to highlight what a save that was, not his mistake.
Just seen the replay... the one you seemed so sure was a moment of madness... What a joke! Not even nearly deliberate and the ball was falling onto his arm, he didn't raise it to the ball.