The Weekend Preview is a blog that aims to provide a different angle on the narrative of an upcoming sporting event.

AFL Round 2: Bulldogs vs. Sydney

AFL Round 2: Bulldogs vs. Sydney

Friday Night, 31st March 2017 at Etihad Stadium

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… 13 seconds, oh it’s on, chase, chase for your life as hard as you can, the flashpoint 5 seconds out, they’ll hang on the Dogs, they are going to hang on, mark this day down Western Bulldogs fans, Saturday May the 2nd 2015.

Anthony Hudson in commentary for Fox Sports
Western Bulldogs vs. Sydney Swans, May 2nd 2015

May 2nd 2015 was the day the Western Bulldogs announced to the football world that they were no longer pushovers. Although as impressive a performance as it was at the time, I don’t think anyone envisaged that 16 months down the line they were going to experience the drama, excitement and ultimate glory that was their 2016 finals series. The Bulldogs securing only their second premiership cup, 62 years after Charlie Sutton led the Bulldogs (including a young Ted Whitten) to the premiership in 1954. And fittingly, the team they beat in the 2016 Grand Final was they same team they beat back in that Round 5 2015 encounter.

However, this 2015 fixture has perhaps been overshadowed by the two classic 2016 encounters between the two teams – the Grand Final and the dramatic SCG clash in Round 15 with Jason Johannisen kicking the match-winner with only seconds remaining. So in case you don’t remember it, here is the closing 2 minutes again:

Delving into the stats of this game, one statistic stands out above all – the contested possession count [1]: Sydney Swans 178, Western Bulldogs 178. In terms of contested possessions nothing could separate the two teams. The Bulldogs had matched Sydney (the renowned contested ball team), contested possession for contested possession. But it is actually the total contested possession count (356) that tells you all you need to know about what type of game this was. To put into context, in that same round the next highest contested possession match total was 299 and the average of the other 8 games was 258. If you like watching fiercely contested footy this was a match for you.

This reputation for contested football for both teams over the last few years is well founded. Table-1 presents the contested possession rankings for 2016, both in terms of average number of contested possessions per game and average contested possession differential per game [2]. In both instances the Swans and the Bulldogs sit in the top 3. What is also interesting is the team that sits in last place for both metrics, but I’ll save that discussion for another day.

 Table-1: Contested Possession Rankings for 2016

Table-1: Contested Possession Rankings for 2016

So now that we have established that their reputation as dominant contested possession teams is justified, how has that translated to wins and losses for both teams? Figure-1 presents the relationship between contested possession differential and match margin for both the Swans and the Bulldogs in 2016 [2]. As is evident by the trend line in the plot, there is a positive correlation between contested possession differential and match margin.

As a league as a whole in 2016, the team that won the contested possession count won the match on 70% of occasions. Hence, although it is still possible to win matches if you don’t win the contested possession count, you are certainly putting yourself at a disadvantage. And the proof was in the pudding in that it was the Swans and the Bulldogs that made it through to the big dance, and both losing preliminary finalists (Geelong and GWS) also ranking well in the contested possession metrics. The two matches between the Bulldogs and the Swans in 2016 were also illustrative. In the Round 15 contest, the Bulldogs won a tight contested possession count 155-154, which translated to the narrow 4 point win. Whilst in the Grand Final the Bulldogs had the edge in the contested footy stakes, winning the contested possession count by 23, translating this to a 22 point win. As summarised in Table-2, despite the small sample size, the trend suggests a relationship between the contested possession differential and match margin between these two teams [2].

 Figure-1: 2016 Season Statistics: Match Margin vs. Contested Possession Differential

Figure-1: 2016 Season Statistics: Match Margin vs. Contested Possession Differential

 Table-2: Match Statistics: Sydney vs. Bulldogs, 2015-2016

Table-2: Match Statistics: Sydney vs. Bulldogs, 2015-2016

So what happened in Round 1 on the weekend? Surprisingly both teams were comfortably beaten in the contested possession count (see Table-3 and Table-4) [2]. For Sydney this was particularly concerning, as their contested possession count (139) matched their lowest total from 2016 (when they were smashed by 42 points by GWS in Round 12). The Round 1 humbling was also against a Port Adelaide side that relied little on their best player Robbie Gray who in 2016 averaged 14 contested possessions per game. Port Adelaide instead spread the load across a fleet of strong bodied midfielders led by Ollie Wines (16 contested possessions), with even ruckman Patrick Ryder getting his hands dirty (13). As for the Bulldogs, they were fortunate the Magpies didn’t make the most of their dominance, with the Magpies entering inside forward 50 eighteen more times that the Bulldogs (62-44) but with only one more scoring shot. The midfield is Collingwood’s strength, so this is no disgrace for the Bulldogs, but they will want to improve on that showing.

 Table-3: Match Statistics: Round 1 2017, Magpies vs. Bulldogs

Table-3: Match Statistics: Round 1 2017, Magpies vs. Bulldogs

 Table-4: Match Statistics: Round 1 2017, Sydney vs. Port Adelaide

Table-4: Match Statistics: Round 1 2017, Sydney vs. Port Adelaide

Were the Round 1 performances player related? Let’s assess the starting 22’s for each team from Round 1. If we sum the average contested possessions per game for the 22 players from their 2016 statistics we have the following predicted contested possession count [3]:

  • Bulldogs = 152
  • Sydney = 156

With both teams having predicted contested possession counts in excess of 150, they certainly had the playing personnel to win the contested ball. So does that make Round 1 an anomaly or a sign of a regression for either team? We may need to see a few more weeks to answer that conclusively, but you can imagine both teams will want to come out and make a statement this week. Although the departure of Tom Mitchell, and the unavailability of the likes Isaac Heeney, Jarrad McVeigh and Dane Rampe through injury from their 2016 Grand Final team surely tips the balance in the Bulldogs’ favour this week. Regardless, I’m looking forward to the contest.

So have I convinced you? Is contested possession a critical metric for team performance? There are doubters out there. So for balance, I’ll give the final word on this discussion to Alastair Clarkson, four-time premiership coach and the best senior coach of his generation:

Contested ball is just a fancy term for everyone in the media. We don’t give a toss about that either.

Alastair Clarkson, 2016

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Post Match Comments: 

Final Score: Bulldogs 16.14.110, Sydney 13.9.87
Contested Possession Count: Bulldogs 169, Sydney 153

So the Bulldogs won the match by 23 points and the contested possession count by 16, maintaining the trend between margin and contested possessions for this match-up. For the Bulldogs the contested possession differential of +16 matched their 2016 average, indicating that they are back on track after a perhaps less than convincing opening match. As for Sydney, they have now had consecutive losses in both match result and contested possession count. A worrying sign as they now face a Collingwood side that although winless has won the contested possession count in both their opening two games. The main problem for the Magpies is capitalising on their midfield dominance. With both teams 0-2, it is a must win for both of them.

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[1] A contested possession as defined by Champion Data is a possession which has been won when the ball is in dispute – it includes looseball-gets, hardball-gets, contested marks, gathers from a hitout and frees for.

[2] Based on data sourced from Match Centre stats on the AFL website http://www.afl.com.au/

[3] For players that did not play a senior game in 2016, their contested possession count from Round 1 was used in the calculation.

AFL Round 3: Port Adelaide vs. Adelaide (Showdown 42)

AFL Round 3: Port Adelaide vs. Adelaide (Showdown 42)

AFL Round 1: Carlton vs. Richmond

AFL Round 1: Carlton vs. Richmond