Sunday, August 19, 2018

AFL Power Rankings: Round 22 2018

You have to beat the good sides to win the premiership. Based on their form so far against the likely finalists, which teams should be a bit worried?



Melbourne’s bizarre season 

Today Melbourne qualified for its first AFL finals series since 2006 with an excellent win against the West Coast Eagles. That win aside though, Melbourne’s struggles against the top sides in 2018 have been well noted. They’ve had twelve wins and one loss against teams that are currently in the bottom half on the ladder. Against teams in the top half they’ve had seven losses and just the one win.

Prior to the Eagles match the gap in the Demons’ relative performances against top and bottom half teams was one of the largest in VFL/AFL history. (See this helpful graph from Insight Lane – by a nice coincidence I had already chosen the topic for this week’s post when this insight was given.) Usually good performances against good sides and not-so-good sides tend to go together. Strangely, two of the largest gaps ever in relative performance have come in the past two seasons – last year it was Port Adelaide who confounded rating systems by destroying ‘bad’ teams and capitulating against the good ones.

Melbourne has been highly rated by my ranking system for most of the season, because of its ability to annihilate lower teams. This has left me feeling more and more sheepish as the Demons have racked up losses against the top sides.

The best way to explain Melbourne’s high ranking is this: the Rankings take into account performances against the whole league, not just the top half. It is true that the Rankings have tended to overestimate Melbourne’s chances against the top teams this season. By the same token though, they have tended to underestimate the Demons’ victory margins against the lower teams.

It’s beating the top teams that matters now – which likely finalists should be worried?

However as we get to the finals series, it’s only a team’s performances against the teams that remain that matter. Based on this, once they get past the joy of qualifying for their first finals series in twelve years the Demons should be a bit concerned about their ability to progress.

Melbourne’s average adjusted net margin this season against the other likely finalists is -8 points. After adjusting for opposition strength and home ground advantage this makes them the equivalent of a below average side when they come up against the best (see table below). Richmond, Hawthorn, and Collingwood all won by large margins against the Demons, and Sydney beat Melbourne last week on its home ground.


For the other likely finalists, Collingwood’s inability to beat the top eight teams has also been well noted. The Magpies have only beaten one top eight team: Melbourne (although they came close to beating Sydney). Their best performances have come against the next tier of sides that are just outside the eight – Port Adelaide, North Melbourne, Essendon, and Adelaide. Against the likely finalists they have been the equivalent of an average side. Collingwood and Melbourne are two of the better sides overall, but their ladder positions have been helped a little by friendly fixtures.

Less well noted is GWS’ struggles against the better sides earlier this season. The Giants were thrashed by Geelong, and were also well beaten by West Coast. They have also lost to Sydney twice. Some of those performances may have in part been affected by injuries, but that may not be much comfort to the Giants as injuries have recently hit them again.

Who has done well against the best?

Minor premiers-elect Richmond has performed the best overall against the top teams. The Tigers have had some struggles outside of Victoria, but they have beaten every team they have played in their home state. Unless they lose in the first week of the finals they will play at the MCG for the duration of the finals series.

Also doing well against the top teams are Sydney, West Coast, Hawthorn, and Geelong, although for somewhat different reasons.

Sydney beat the Eagles both at home and away and has also beaten GWS twice this season. Most notably the Swans have had excellent form away from home, beating Geelong, Hawthorn, and Melbourne.

West Coast’s best win for the season was their big win against Richmond at home. They have also shown they are capable of winning in Victoria against good opposition by beating Hawthorn and Collingwood there.

Hawthorn thrashed Melbourne, and also easily beat Collingwood in the first match of the season. The Hawks beat Geelong twice (albeit narrowly), and have generally been close in their losses against the top sides.

Geelong is the second-highest team on the Rankings but will likely finish in seventh or eighth spot on the ladder, in part because of their tough fixture. The Cats’ form against the top teams has been fine: they thrashed GWS, and have been good or at least OK in most of their matches.

You may step it up though

So should we just be waiting for the seasons of Melbourne and Collingwood to come to an abrupt end? Of course not. Last year for example we saw Richmond play considerably better against teams in the finals series than they had done earlier in the season, including a massive (home ground advantage aside) 124 point turnaround against Adelaide. The Western Bulldogs substantially stepped up their performances in September the year before.

Melbourne and Collingwood are good teams. They may even be capable of matching it with the best teams. They just haven’t given a whole lot of evidence during the season that they can yet.

2 comments:

Gordon Smith said...

Thank you, Troy, for your conclusion. I’m not particularly a Demon or Magpie fan, but it’s refreshing to have someone say what the stockbrokers are required to admit: “Past performance does not guarantee future profits.”

Troy Wheatley said...

No, indeed - if it did, every one would be in the same position forever.