This is an excellent example of a tackle technique Walmart where the players are not at full intensity, but the accuracy of what they're doing is very important the players making a good tackle. Then he is taking up a strong position to contest for the ball before moving on to the next tackle. Attacking and defending players experience a range of angles rather than just running straight at them. It's also enforce the scanning ability from the tackles. It's important to note that all players are constantly active during this exercise. If you have more players, you can have more tackles in the middle.