AFTER an impressive win over Geelong in week three, expectation was that Carlton was on the improve. But that hasn't eventuated.

A shoulder injury to captain Kerryn Peterson in the opening minutes of the club's week four match against Richmond has exposed the disorganised underbelly of the Blues' defence, and made it particularly vulnerable to marking targets in opposing clubs' attacking lines.

Key defender Harriet Cordner is playing well, averaging a career-high 7.7 intercepts and 12.7 disposals per game, but is often left as a lone hand in combating dangerous tall forwards.

Gab Pound, standing at 163cm, has been asked to play on tall opponents in recent weeks since Peterson's injury, and the rest of Carlton's height down back is relatively inexperienced.

Madeleine Hendrie, Ciara Fitzpatrick, and Genevieve Lawson-Tavan have played an average of 14.3 games between them, with the unit's chemistry and organisation found lacking.

Carlton's defensive downturn

*Carlton played three games across weeks four and five

In Carlton's three most recent games, it has conceded nearly four more goals per game, with key forwards doing more than half of the damage. Across those games the Blues have conceded 26 goals, 15 of which have come from tall forwards, with Caitlin Greiser and Tahlia Randall each kicking three, Katie Brennan, Emma King, and Gemma Houghton kicking two each, and Julia Teakle, Ashleigh Saint, and Olivia Levicki with one apiece.

There have been two contrasting ways in which forward lines have exploited Carlton's defensive disorganisation. The first is trusting that the Blues will overcommit in an aerial outnumber, leaving runners on the deck to clean up and goal. Tess Craven's first-quarter goal back in week five is just one example of this.

The other is by isolating Carlton's defenders in one-on-one situations, and backing their own experience over their direct opposition.

There is certainly an element of luck involved, with the Blues being forced to face Richmond, North Melbourne, and Port Adelaide without Peterson at the helm, all three clubs boasting dangerous, dynamic forward setups.

The most interesting statistical shift for the Blues from their first three to most recent three games this season, however, is a dramatic increase in opposition goal assists. This metric growing from 1.7 per game to 6.3 is emblematic of opposing forward lines' ability and willingness to share the ball around.

Wingers and midfielders are engaging damaging attacking run against the Blues, with their direct opponents unable to impact defensively to support Carlton's backline.

It is a problem that doesn't have an easy or quick solution, and unfortunately that means warning bells with a match against Brisbane coming on Saturday evening.

The Lions are yet another side with three dangerous tall forwards in current season leading goalkicker Taylor Smith, Dakota Davidson, and Eleanor Hartill, with smaller options Courtney Hodder and Sophie Conway also able to hurt you on the deck.

Realistically, the best way to stem the flow is to urge greater pressure up the field from the Blues. This can force poorer, less effective forward entries from the Lions, while Carlton's midfield/wing contingent must force its direct opposition to be accountable.

Wingers and midfielders playing aggressive, attacking footy is a brand of the Lions, but if the Blues are to allow that free attacking run from the middle, they could very well be looking at another percentage hit.