Defence rules in the AFL.
So Richmond, Port Adelaide, West Coast or Geelong will win the premiership.
That's if recent history is a rule.
The past three premiers have been ranked top-four in defence at the end of the home-and-away season.
The Tigers, Port, Eagles and Cats are the top four in points conceded entering the business end of this season.
They're where every AFL coach wants his side to be: stingy, hard to score against.
"Defence has moved up. All 18 clubs have got better at defending," Greater Western Sydney coach Leon Cameron said after his victorious Giants restricted Port to just eight goals.
"They tackle better. Defend better."
Not since Hawthorn in 2014 - middle flag in a three-peat - has a club ranked outside the top four in defence won the flag.
The 2014 Hawks were ranked sixth.
However, they were highest-scoring, powered by slick ball use from Sam Mitchell, Cyril Rioli, Luke Hodge and Jordan Lewis in their primes.
With modern defending so solid, Giants coach Cameron reckons that slickness of ball movement is what is needed to crack the defensive codes.
"The hardest thing now is, how do you counteract that (defence) and make better decisions going forward?" Cameron said.
"Everyone wants that money-ball kick or money-ball decision more than not."
TOP-FOUR DEFENCES (end of home-and-away rounds):
2018: Richmond, Port Adelaide, West Coast, Geelong
2017: Sydney, Port Adelaide, Richmond, Adelaide. Premiers: Richmond beat Adelaide
2016: Sydney, Geelong, Western Bulldogs, GWS. Premiers: Bulldogs beat Sydney
2015: Hawthorn, Fremantle, Richmond, West Coast. Premiers: Hawks beat West Coast
2014: Sydney, Fremantle, Port Adelaide, Essendon. Premiers: Hawthorn beat Swans. Hawks were ranked sixth defensively and conceded 68, 94, and 74 points in three finals to win the flag.
