The 26-year-old is to have a knee reconstruction, with his recovery expected to take about six months.

New Zealand's first match at the tournament - against Argentina - is five months away on 20 September, with the final on 31 October.

Cruden was the starting fly-half in New Zealand's 2011 World Cup final triumph.

He has collected 37 international caps, most recently in his nation's 24-21 win over England in November, and scored 280 points for the All Blacks. Cruden gained his place in the side for the 2011 final after injuries to first and second-choice number 10s Dan Carter and Colin Slade.

Cruden himself was forced off in the first half of the 8-7 win over France with a knee injury, leaving Stephen Donald - who had been on a fishing holiday at the start of the tournament - to kick the decisive penalty. (BBC)