In 2016 I remember much being made of Hawthorn shutting down Nat Fyfe with their ferocious pressure, clips showed 3 Hawthorn players mugging Fyfe every time he touched the ball. Now the Bulldogs followed by Richmond have made this an art form. Every time any opponent touches the ball they are mugged. It demands a fearsome level of fitness and discipline. I remember Tommy Hafey changed the game by demanding higher levels of fitness from his players. Players were encouraged to stick to a packet a day and to follow the maxim introduced infamously at the MCG (in the early 70s the MCG brought in a one slab limit per person you could bring to the cricket or footy) so a slab a day maximum. His demands drove 2 fine athletes in the Whale Roberts and Bones McGhie to try skip a couple of circuits of the tan during a pre season run, alas for them Tommy noticed them missing and walked the tan and became suspicious of a rather large pile of leaves... Tommy changed the sport, Clarkson and his coaching progeny are constantly shifting the bar. The new style does seem built on extreme fitness, like with Fyfe no chance of showing your superior skills if you have no time to use them. Seems the AFL may need to move soon on further reducing rotations to tire players more. One thing we know is that coaches will find the answers and the game will change again.