While the grunt work is typically done by the midfield of an AFL side, the heavy lifting can often be done by the backline, especially for teams at the lower end of the ladder.
Premiership defences require potent key defenders, intercepters and running ball-users to provide an offensive threat.
Geelong were an unstoppable force out of defence last season, with De Koning and Stewart constantly preventing chaos and allowing ThuoyThou, Guthrie and others to control the ball effectively.
Melbourne were unbeatable at their best in 2021 with Lever, May, Petty and even Gawn maintaining control of the game with their aerial presence while Salem, Brayshaw and Rivers inflicted damage by foot.
This list will help you decide which team will be the immovable object in 2023 and here we look at the backlines ranked 12-7.
SEEL: Every AFL team's backline ranked PART I
4. (9th) Port Adelaide
The Power have a steady mix of talent on their defensive line and were able to prevent big scores from their opponent last season, conceding only 74.4 points per game.
They have the capacity to limit opposing power forwards with Aliir Aliir being one of the league's best intercept defenders when healthy while Tom Jonas and Tom Clurey round out an effective tall defender slot.
Darcy Byrne-Jones and Dan Houston carry the load at ground level and are both coming off quality seasons with Houston's offensive launch and Byrne-Jones' lockdown ability.
Ryan Burton and Riley Bonner will have an intriguing battle for the final spot in the back six throughout the year, they both provide some extra handy ball use out of defensive 50.
Jase Burgoyne and Lachie Jones add to their depth and are notably popular choices to round out the back options.