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AFL Round Two: Collingwood’s Defensive Unit

(Photo credit: AFL Photos).

We welcomed back the 2020 AFL season with open arms on Thursday night, plenty having already been said about the game.

Collingwood controlled possession early as Richmond’s pressure lacked. Richmond’s pressure went up as Collingwood couldn’t control possession like they did earlier. The game was played in Richmond’s half. Collingwood was holding on.

What fascinated me above all else was the solidity of Collingwood’s defensive unit, and how the Pies contrasted the Tigers in their defensive half.

Collingwood’s Defensive Unit

Overview

I won’t spend too much time on an overview. If you’re reading, you’re most likely aware of the players referenced and their corresponding ability.

Subjectively, Collingwood’s defensive unit is among the competition’s best, boasting a great balance of aerial and ground talent.

The likes of Jeremy Howe, Darcy Moore, Jack Crisp and Brayden Maynard are likely to grab most of your attention. Howe and Moore are among the competition’s very best intercept defenders, while Crisp and Maynard provide great avenues for clean ball use out of defensive 50.

Accompanying these four on Thursday evening were former Bulldog Jordan Roughead, midseason pick up John Noble and key defender Jack Madgen. The impact of these players is often understated, and was so again on Thursday evening, especially given the performances of Roughead and Madgen more specifically.

Comparison with Richmond’s backline (R2, 2020)

Against Richmond, Collingwood’s defensive unit were forced to occupy a deep-lying field position, contrasting that of the Tiger’s defensive unit who were able to set themselves higher up the field thanks to their corresponding pressure around the contest. Richmond generated twelve more inside 50s (I50s) than Collingwood, which may reflect one possible metric we can use to illustrate how the Tiger’s defenders were able to sit further afield, while Collingwood defenders were forced to defend under siege. Richmond’s defensive unit (Astbury, Baker, Broad, Grimes, Houli, Short and Vlastuin) combined for +5 intercepts and +2 inside 50s, compared to Collingwood’s defensive unit on Thursday evening.

In 2019, Richmond ranked 15th in the AFL for rebound 50 differential, also illustrating a lack of time spent in their defensive half, which would allow their defenders the opportunity to congest free space ahead of them, playing further afield.

The video below highlights some instances of how Richmond’s defenders were able to defend a higher line than Collingwood, generating valuable turnovers and repeat I50s. On Thursday evening, four of Richmond’s five goals were generated from turnovers in the midfield.

What was noticeable Thursday evening?

Richmond’s I50 scoring efficiency

Richmond finished with an I50 scoring efficiency of 25% against the Pies, well below its 2019 average of 42%. This metric is aimed at identifying how often a team scores per I50, in which Richmond ranked the lowest of all teams during the restart round (followed by Adelaide who scored at a rate of 30% in their loss to Port Adelaide).

Rust could be one source of blame for such a low rate of scoring efficiency, though more likely is a strong defensive performance by Collingwood who were able to repel numerous Richmond repeat entries.

The Tigers dropped below Thursday evening’s rate of efficiency just once during the 2019 season, when they managed to register scores on only 23% of I50s against Geelong in Round Twelve (67-point loss). In addition to this rarity, only four other games last season saw teams register an I50 scoring efficiency of below 25% (see table below), further highlighting its rarity for a team who managed to draw on Thursday evening against a high-calibre opposition.

(Funnily enough, GWS also registered a scoring efficiency of 25% in last season’s Grand Final loss to the Tigers).

AFL teams that registered an I50 scoring efficiency of less than 25% (2019)
RdTeamVersusI50 Eff%Margin
15PTAWBD23%-25
12RICGEE23%-67
2MELGEE22%-80
21GWSHAW21%-56
7FREADE18%-17

Averaging a score every fourth I50 isn’t great (AFL average in 2019 regular season was approx 43%), but it’s not the end of the world for Richmond, given that the Tiger’s renown style of play relies more on the volume of I50s, rather than their efficiency up forward. This is achieved by creating turnovers up field and generating repeat entries I50.

In 2019, the Tigers ranked thirteenth for average I50 scoring efficiency, while ranking 3rd for I50s differential (during the regular season), illustrating their intent to generate more I50s than their opposition, even if that means scoring on less of those entries. In only five of the Tiger’s seventeen wins last season, did they register less I50s than their opposition.

Last season saw a couple of teams mimic this style of scoring. The Western Bulldogs, who ranked second for I50 differential, also ranked twelfth for I50 scoring efficiency, while Port Adelaide ranked first and fifteenth in the respective metrics.

Clubs like GWS and Geelong contrasted the likes of the Tigers, Bulldogs and Power. The Giants ranked twelfth and first in I50 differential and I50 scoring efficiency, while the Cats ranked seventh and second. For the good teams there’s more than one way to score, usually either through high volume, varying efficiency (i.e. Richmond); or lower volume, excellent efficiency (i.e. GWS).

So I’ve probably oversold the case for Richmond’s poor night, and haven’t focused on Collingwood’s defensive unit whatsoever in relation to the Tiger’s scoring efficiency. I’m still rather new to this, and clearly can get somewhat sidetracked.

I don’t have any outstanding metrics to flaunt in favour of the Pies in this section. I’ll call on the eye test. The Pies seemed to repel entry after entry despite the significant pressure repeat entries cause a defending side. The scoring efficiency metric in itself is not meant to highlight the dominance of one side’s forward or defensive unit, rather reflect a balance of the two. On Thursday evening (at least for me), that balance was tipped in the Pies’ defender’s favour.

Collingwood’s aerial balance & contest shape in defensive 50

Richmond managed just four marks I50 on Thursday evening, thanks to a mix of Collingwood’s intercept marking and steely defending.

Considering the conditions were slippery under foot, along with a congested Richmond forward 50, there are a number of factors that contributed to the Tigers only managing a mark every eleven entries I50.

Comparing again to last season, Richmond averaged +1.45 marks I50 during the regular season compared with their weekly opposition. This increases to +3.69 when looking at Richmond wins only. The correlation between the Tiger’s marks I50 differential and overall score margin returned an r squared value of 0.68 (2019 regular season, small sample), the equal-third highest in the competition. Though correlation doesn’t determine causation, ten of the eighteen AFL sides in 2019 registered r squared values above 0.50, illustrating the metric’s potential importance as an indicator for success I50.

One way Collingwood negated Richmond’s supremacy in the air, was by often (successfully) sealing their opposition out of marking contests. This art is something Collingwood obviously preaches and trains, along with (I’d guess) every other AFL club. Some may argue the action as blocking, or an illegal impediment, but if executed correctly, teams are able to generate valuable intercept marks easier, reducing the chances of opposition players roving aerial contests and scoring.

The roles of Madgen and Roughead see them frequently sealing their opposition player out of a marking contest, allowing for the more aerially-gifted Howe and Moore to come across a contest and mark (or spoil, depending on circumstances, location on ground, etc). I’ve found a couple of instances you can watch below (including Howe sealing for Madgen on one occasion). I’m sure there are also plenty of examples out there of Richmond/West Coast/Brisbane achieving similar results with Grimes/McGovern/Andrews/etc (just to name a few).

The act of sealing seems simple, but requires well-trained execution. Madgen and Roughead, given their size, are able to initiate body contact with their direct opposition to mitigate their ability to fly for a mark. This requires a clear view of the ball ahead and great timing, placing themselves in front of their direct opposition at the time the kick is launched to ensure they look like they’re contesting the mark.

With the presence of either Madgen or Roughead at a contest, along with Howe or Moore, Collingwood were able to repeatedly achieve great contest balance in the air. This occurs when players are able to organise themselves to ensure one player flys for the mark, while others seal. This balance continued at ground level, with players such as Crisp, Maynard and Noble, along with support from Collingwood wingmen and midfielders (i.e. Tom Phillips, Chris Mayne, Steele Sidebottom), ensuring Collingwood often outnumbered Richmond on the ground at contests if no mark was taken. Achieving this balance at defensive contests is vital to a team’s success in limiting scoring opportunities. Midfielders who work hard defensively provide crucial outlets for defenders pressured by opposition forwards, which then triggers cleaner rebounding opportunities. Last year Brisbane’s Mitch Robinson summed this up perfectly in a Fox Footy article discussing the role of wings in the AFL. You can also watch an example from Thursday’s game below.

“Be the first midfielder to get back to help support the defenders on a stoppage loss. This is highly regarded, because you can outnumber the opposition forwards and create release options for your teammates…”

Mitch Robinson, Fox Footy
Collingwood’s defensive unit going forward

As mentioned earlier, Collingwood’s defensive unit contrast Richmond’s in some capacities, one being field position.

Despite playing a deeper field position, Collingwood defenders combined for ten score involvements, featuring on all but one of their side’s scoring chains. On the other hand, a Richmond defender featured on just five of the Tiger’s eleven scoring chains, half that of Collingwood’s defensive unit. This helped further highlight the contrasting styles these two teams play. Richmond are often more likely to generate scores from turnovers through the midfield and up forward, rather than through intercept possessions made by defenders. As for Collingwood, intercept marks that quickly turn into blistering counter-attacks mean defenders can be more likely to be involved in scoring chains at times.

Overall

Collingwood defended extremely well given their situation on Thursday evening. Without the ability to find position further up field, the Pies defended their backyard entry after entry, against an admittedly wasteful Richmond at times.

What may come across as a puff piece for the seven Collingwood defenders shouldn’t takeaway any praise for the Tiger’s back six either. A key reason as to why Richmond strangled Collingwood in the second half was their ability to yes, pressure the ball at the source and stem Collingwood’s ability to rebound, but also their defenders ability to ensure any Collingwood exits from their defensive 50, were mostly sent straight back into the cauldron.

Upon rereading the piece here late Wednesday night, I’m starting to see the title of this piece may be slightly misleading. I hope my Round Two musings haven’t led you astray, and that you were able to follow some sort of logical path to the conclusion of this piece.

There are a number of limitations involved when writing a piece of this nature using public resources. For example, analysing a defensive unit as simply seven players doesn’t take into account the potential for other players to rotate through the back half, though most teams will operate with a strict seven-man rotation. This is just one example of a potential limitation.

2019 season statistics are referenced from my own database using data sourced from the reliable afltables.com. Statistics used from Thursday evening’s season restart were sourced from AFL.com.au.

What’s next?

Well if you got this far, you might as well hear what’s next.

I’m hoping to continue with one piece per round, shedding some light on other games in the coming weeks, and not just necessarily games of similar magnitude to Thursday night’s restart. My motivation has been all over the shop, and has probably been the biggest contributing factor as to why this piece has been released the night before Round Three, and not earlier. We’ll see where we end up this time next week.

There’s also no time like the present to link two pieces I wrote just over a month ago now. The series was going to be known as ” The NEAFL Sample “, discussing a couple of recent AFL draftees and their performances in the NEAFL last year. So far I’ve covered Connor Budarick (Gcs) and Keidean Coleman (Bri). I basically run over some statistics and footage of the two prospects for no good reason whatsoever. I’ll hopefully get time to talk about Malcolm Rosas Jr (Gcs) in the near future too.

If you’ve enjoyed what’s written above, we’re also on Twitter & Instagram. This project is in its infancy and any support on establishing these platforms would be greatly appreciated. I’ll start to circulate content in the coming days. I’m also all ears to anyone wanting to discuss what’s written above, or other projects in the pipeline. Thanks again.

ftballextension@gmail.com