Does form actually matter in the Showdown?
SHOWDOWNS are the biggest event on the South Australian football calendar, with the matches between Adelaide and Port Adelaide often going down to the wire. But, despite the belief of many that prior form entering Showdowns ‘doesn’t matter’, is it actually true?
Die-hard Crows fan Matteo Gagliardi takes an in depth and *unbiased* look at what the stats say.
During Showdown week, you can only take one thing for granted.
It’s that someone, somewhere in South Australia, has said or heard some variation of the sentence: “Form means nothing when it comes to Showdowns”.
Of course, we all know form means nothing in a Showdown because we all remember that time our team was odds-on to win but got pantsed in the most unexpected and embarrassing fashion.
Or that other time we looked like winning, but were thwarted by an errant bounce of the ball or a banana kick that defied the laws of physics to end up as both a goal and a behind, simultaneously.
There’s a different psychology to Showdowns, so much so that some fans elevate the significance of the fixture up to the level of the Grand Final, or near enough to it.
After all, in a two-team town like Adelaide, footy fans exist in a permanent tribal Cold War that boils over into fully-fledged hostilities twice a year.
Because of this, the usual considerations that go in to forecasting who will win are thrown out the window – or so the sentiment goes.
But is this just a wives’ tale or is the unpredictability of Showdown results actually borne out in the data?
I cross-examined Showdown results with three measures of favouritism to find out.
The form worm
First of all, I took a close look at the Showdown win/loss ledger. A good, long, hard look (it looks better and better each time I do).
The “form worm”, as I like to call it, provides a good visualisation of favouritism playing out over extended periods of time, because of the clear periods of dominance.
Port Adelaide holds the record for most consecutive Showdown wins, with seven between 2000-2003, while Adelaide has reigned in the win/loss differential three times; most notably in two spells of momentum between 2005-2008 and 2015-2019 (thanks, Ken Hinkley).
These multi-year purple patches roughly map on to the seasons in which the respective teams held superior ladder positions.
Port finished higher up the ladder than Adelaide each year between 2001-04 (a period in which they were minor premiers three times and premiers once), with Adelaide returning the favour in all but two of the years making up their domination spells (2007 and 2018).
In fact, across each of the 22 completed seasons in which a Showdown has been played, the team that finished higher up the ladder at the end of the season won 31 of a possible 45 Showdowns during that season.
Some might argue it’s pointless to talk – in hindsight – about a team’s form across a whole season when evaluating its predictive capacity for any one individual win, though.
And, of course, teams that win Showdowns are likelier to finish higher up the ladder than their beaten opponents, as it gives them an extra “W” next to their name on the ladder and puts an extra “L” next to that of their rivals.
But, if anything else, this is a good measure of form over the long run.
The cream never stops, stops, stops ‘til it rises to the top, top, top
Perhaps a more appropriate measure of form in the moment is the live ladder position of each team heading in to the match.
Interestingly, across all 46 Showdowns, the team sitting higher on the live ladder has won 28 times for a strike rate of 60.8 per cent. This is pretty telling.
Of course, live ladder positions mean little when the Showdown is played early in the season (for instance, it’s been held seven times in round three and twice in round two).
Unsurprisingly, 11 of the 23 Showdowns held in the first half of the season have been won by teams lower on the live ladder – almost a 50/50 correlation.
Conversely, 15 of the 22 Showdowns held in the latter stages of the year were won by teams higher on the live ladder (a conversion of 68.2 per cent).
This tells us that when we have a bigger sample size of results to inform us who’s really “in form” over a longer period of time, the better we’re able to predict who the winner will be.
Curiously, Port Adelaide won as many Showdowns from a relatively lower position in the live ladder as from a higher position (11 each), with most of the former occurring in the first Showdown of the year (seven).
Meanwhile, 17 of the Crows’ 24 Showdown wins were from superior live ladder positions, and most occurred in the second Showdown of the season. But this might be because the Crows assumed a higher live ladder position in the lead up to 28 Showdowns, compared to Port’s 18.
Match outcome compared with live ladder position
|Wins from a higher ladder position||Wins from a lower ladder position||Total|
Taking it week by week
Ladder positions don’t necessarily capture momentum heading in to a Showdown clash, especially if one team has an easier draw. For that, I had to consider the win/loss ratio from the preceding month (or so) of matches.
This was no straightforward task, given the fixture has been contested twice in Round 2, seven times in Round 3 and twice in Round 4.
So I broke the analysis down into three categories: the teams’ form over the preceding two weeks, the preceding three weeks and the preceding four weeks (whenever possible).
Average number of wins from weeks preceding Showdown
|Previous 2 weeks||Previous 3 weeks||Previous 4 weeks|
For each category, the winning team typically outperformed the losing team in the weeks leading up to the match, on average.
However, the median form differential for each category (representing the most common recent win/loss differential between the two sides) was zero. This suggests both sides often headed in to the Showdown with the same level of momentum.
In saying that, when there is a form-differential imbalance at play, the out-of-form side lost more than they won.
In such cases, the teams with a negative form differential from both the preceding two and three week periods ended up winning just eight out of a possible 28 Showdowns; while the teams with a negative form differential from the preceding four week periods ended up winning nine out of a possible 24 Showdowns.
The most memorable underdog victory, in this respect, was Showdown XXIX in 2010.
Port went in to the 29th Showdown having lost nine consecutive matches, yet won in Showdown legend Josh Carr’s final match of his 207-year career.
Alas, the most significant predictive factor in Showdown factor was whether Josh Carr was playing, given Port won 10 out of 10 Showdowns in which he was playing.
So does form matter when it comes to predicting Showdown results?
Judging by the indicators mentioned above, form does matter to a considerable degree – both when considering the longer term picture and the present. At least, it matters more than it doesn’t matter.
Ultimately, we believe form doesn’t have a bearing on Showdown results because we remember the exceptions to the rule in their morale-shattering infamy more than we do the proof itself.
But the test is to compare these statistics with the norm for the league – or perhaps, to compare them with similar data points (such as those from the Perth Derby). This will have to be a challenge for another day.
P.S. what’s my prediction for this week?
Well, Adelaide is enjoying an extended Showdown purple patch and, judging by the data, it does like to play the second annual Showdown, especially when it’s sitting higher up on the live ladder.
It’s also enjoyed the superior form over the past month.
Yet, I’m not dumb enough to incite the wrath of the footy gods by tipping us.
Go you Crows!