Nishimura is always smiling, even when he's not sure about a call he has made but let's be honest, how often does that happen?
He kept everything under control and was on the spot immediately. His assistants were right on the ball, just like he was. Overall performance was just as good as it was in the World Cup.
The officials for the Quarter Finals are most likely the referees who's nation will make the Semi Final so my guess is that a Quarter Final will probably be Nishimura's last match of the 2011 AFC Asian Cup.