Analysis: Tonga defence coach Grant Doorey on how teams can defend rucks and scrums

With the use of Tactic Pro software, Liam Dunseath from Sport Video Analysis catches up with Grant Doorey, the Tonga assistant coach, to talk ruck and scrum defence on behalf of RugbyPass to help explain to players and coaches the roles and responsibilities when defending an edge ruck and a midfield scrum.

"When defending an edge ruck normally you will position a player on the short side labelled “-A” but you can choose what you like. From the ruck outwards, player positions in our clip are A to G. Each ruck is different and the one used here is No9 who passes directly to No10 with a pod outside him, who are usually forwards.

"Notice the second distributor out the back usually happens to be the No12. The ruck set-up or picture could be quite different if the No10 had players inside him - for example, the blindside winger or if it were just a pod of three players directly from No9. Therefore, whatever the picture presented, the roles and responsibilities for the defenders change depending on what the attackers choose to do.

"When attackers have gained a midfield scrum, have your backs recognise how their backs set up. In this instance the attackers have chosen a 4/2 split with four on the openside and two of their backs on the blindside. The defending team has two backs either side. However, the No15 roams and can push up to cover the edge at the last minute.

"Notice how the No9 rides high to put pressure on the first receiver, allowing the defending No12 to defend the player outside. This utilises the extra players to cover the zone.

"Although it may look like a 3/2 split it actually gives us a 3/3 split. The defending No10 drops to cover the back field along with the blindside winger if the defending No15 goes up to cover the outside space.

"We encourage coaches and players to change positions to have a feel for each role and promote coaches to change formations within training sessions."

• Be sure to drop Liam Dunseath and Grant Doorey, the Tonga assistant, a line to sportvidanalysis@gmail.com with any tactical rugby questions