Place 1 tackle bag on each corner of the channel and a contact shield 10m down the channel in the middle. Place a ball at the top of the channel in the middle. 4 players working in pairs start at the top of channel. The rest of the players are split into 2 groups on either side of the channel 10m down. Drill starts with the 2 players at the top making a tackle on the bags and getting up picking up the ball and attacking down the channel. At the same time this happens 1 player from the side drives the shield out of the channel and defends the 2 coming down in a 2v1. Once he has been beaten he turns to join the other 2 attacking down. Simultaneously another 2 players have run down the side of the channel,tackled the bags and are coming up the channel to defend in a 3v2.