Prince William left nursing his crown jewels

Prince William gave an audible yelp and winced as a ball thrown by a schoolboy from Pakuranga club in Auckland hit him between the legs.

According to The Sun, the 27-year-old heir to the British throne joined the youngsters on the pitch of Auckland's Eden Park stadium which is undergoing a 110-million-pound redevelopment and will open later this year.

The youngsters had been playing mini rugby at the stadium which will be the key sporting venue for the 2011 Rugby World Cup being hosted by New Zealand next year.

The prince's love for the sport saw him visit New Zealand in 2005 to follow most of the matches of the Lions tour against the country's famous All Blacks.

The royal also showed his support for next year's major tournament by wearing a Rugby World Cup promotional jersey with the word 'Wales' emblazoned on the back.

Helping to take the youngsters through their paces on the pitch was one of the South Pacific nation's rugby stars Ali Williams.

The All Black joked about meeting the prince and said: "The last time I met him I told him he was losing his hair, this time I haven't done so because I'm in the same boat as him."