This is a series of exercises to help improve your defensive line. It starts with a simple tackle technique exercise note that as a safety measure the coach is dictating which shoulder to attack. This also ensures that both shoulders can be worked. The players move on to the next station, which is against live attackers The Defenders focus on scanning and spacing as well as the tackle technique. The play moves on to a further phase where more attackers play the same way. Defenders need to reorganize quickly to ensure that they're scanning. Their spacing is correct, and they're staying aligned.