The Blitz defence is a defensive method used in sports including American Football and rugby union.
In many ways, the blitz is similar to the defence used in rugby league which can be explained by Edwards's background in that code.
In a blitz defence the whole defensive line moves forward towards their markedman as one as soon as the ball leaves the base of a ruck or maul.
However, the defending team can be vulnerable to chip kicks and any player breaking the defensive line will have much space to play because the defence are running the other way and must stop, turn and chase.
The term blitz defence is a defensive play in American Football, where the defence players (usually Linebackers) pile forward against the offensive line en masse in the hope of tackling the Quarterback while he is still in possession of the ball.