Yamamoto worked with Italy coach Cesare Prandelli in his role as the personal therapist for Japan superstar Hidetoshi Nakata, who became Asian football's biggest star during a successful seven-year spell in Italy. He later followed Nakata to Sam Allardyce's Bolton Wanderers in 2005. The story came full circle when, having joined West Ham in 2009, Big Sam joined the therapist in east London two years later!
He told whufc.com: "I am excited because this is my first World Cup. In 2006, I went to Germany as a supporter to watch, so this will be the first time working at a World Cup and it will be a great experience.
"It's very, very interesting because the first game is against England. Prandelli is very strict and very professional and I like him and his methods. I also know some of the players - the defender Giorgio Chiellini and left-back Manuel Pasqual - from Fiorentina. Maybe I know three or four of them.
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