Van Persie - who will be the Holland coach's captain when the World Cup kicks off next month - laid bare the volume of training the 62-year-old demands.
'Every training session is very intense. He is on our backs every minute. There is no space to relax, he demands full focus,' Van Persie told The Sun.
'We work very hard for a maximum 1.15 hour, never longer. But these 75 minutes are enormously intense.'
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