Underhill had a try disallowed for offside against the All Blacks last year

World Rugby has discreetly changed the offside law before the Guinness Six Nations to avoid a repeat of the row that erupted after England were denied a potentially match-winning try against New Zealand at Twickenham in November.

The governing body is not supposed to change the laws in a World Cup year and it described the rewording of Law 15.4 as a “revision” designed to end the confusion that arose in the autumn.

The key amendment is that the offside line at a ruck will no longer be based on the position of the “hindmost foot” but on the “hindmost point of any player from either team”. That can mean an arm or a head; it does not have to be a foot on the