Posts Tagged ‘Possession’

2015 Season Review – Part I

October 29, 2015

Reviewing the major statistics – Attacks, Attack Rates, Shots, Shot Rates & shooting accuracy – from the season just gone, and comparing them to previous seasons, has become a staple of the blog. We do it for two main reason; the first to see if there are any major trends, or indeed areas of complete randomness, jumping out whilst the second opens a window on any elements we should be taking a closer look at.

We tracked where attacks originated for the first time in 2014. This was extended in 2015 to cover all possessions. This enables us to have a complete picture of an average (see NOTE 1 below) Championship game. How often teams have the ball, where those possessions emanate from and what they do with them.

Given this expansion I am going to split the review into two parts; below concentrates on everything up to shooting whilst the second piece (due soon!) will focus on shooting trends and accuracy. So without further ado here are the overall returns up to the point of shooting

 

Year Possessions Attacks Attack Rate Shots Shot Rate
2012 35.3 27.0 76.6
2013 36.3 28.3 77.8%
2014 39.8 30.9 77.5%
2015 49.7 36.8 74.0% 27.8 75.7%
avg 37.0 28.5 76.9%

 

Possessions volumes & origination

How a possession is defined is expanded upon within the definitions page but essentially a possession starts with gaining “control” (see Note2 below) of the ball and ends with either a shot or the opposition gaining control of the ball (a turnover). For the sake of this piece all turnovers are equal – whether forced or otherwise – with the only defining characteristic being where on the pitch control of the ball was obtained.

On average a team has the ball ~50 times (49.69 to be exact!) a game. This has always seemed low to me – essentially 2 possessions every 3 minutes allowing for injury time. I guess it emphasises the need to squeeze the most out of each possession though as ever we must be wary of averages. Especially averages built on one year’s data.

Where this single piece of information may be of most use is when chasing (or defending) a lead with “x” minutes to go. You can extrapolate how many possessions you’ll have; how many shots; what you need to break your way; go for points or when to push the “go for goals” button. Game endings can take on a life of their own but knowing you’ll have 10 possession in the last 15 minutes gives you a good starting point.

Where the possessions emanated from are listed below

 

Possession Origination # % all possessions
Own kickout 16.0 32%
Opp Kickout 6.9 14%
T/over own 3rd 17.2 35%
T/over mid 3rd 6.1 12%
T/over opp 3rd 0.9 2%
Other 2.6 5%

Essentially one third of all possessions come from a team’s own kickout, one third comes from ball gained inside a team’s own 45 with the remaining third spread across the game. There is huge emphasis placed on kickouts – both your own and the opposition’s – but teams get as much ball up to the opposition’s 65 from broken play as they do from kickouts. Do teams place as much emphasis in moving the ball, or defending counter attacks, as they do on kickouts? Does the general commentary? I’m as guilty as anyone. Tracking kickouts is easy but how (and why?) teams are able to move the ball in broken play is every bit as important.
 

Attack & Shot Rates

Last year we saw a spike in attacks; rising 11% from 35.80 in the two previous years to 39.83 in 2014. At the time quite a bit of the increase was being attributed to the black card (well the numbers weren’t used in the wider commentary – it was more the black card being acclaimed for leading to open play) however here on the blog judgement was reserved. The black card was part of the reason but it could as easily have been a one year outlier as much as anything.

That reticence seems well founded now as the 2015 average attack numbers have dropped back to 2013 levels. Looking across the four years a team will create an average of 37.0 attacks and, using 2015 data only, 74% of all possessions end up as an attack.

From 2012 to 2014 the average number of shots per game rose from 27.0 to 30.9 – a 14% increase. Over that time there had been a rise in shot rates but nowhere near the 14%. Instead the increase in shots had risen in line with the volume of attacks (with a small bounce from increased efficiency as the shot rate went from 76.6% to 77.5%).

In 2015 the number of shots per game dropped ~10%. As we can see from the above this is to be expected when the number of attacks drops but on top of the drop off in attacks there was also a drop off in the shot rate. For the first time in four years the Shot Rate came in below 76%. Again this is one of those movements that is probably more of a blip, or general randomness, but it is still worth monitoring. The sample size – 1,446 shots in 2015 & 4,246 in the previous three years – is robust.

So there we have it. On average a team has 50 possessions a gam converting 74% of those possessions to an attack and 77% of those attacks to a shot leaving a total of 28.5 shots a game. What teams do with those shots will be expanded up in Pasrt2 of the review.

Note1: Averages hide a lot and the fact that Dublin have been the pre-eminent attacking team in the period that these returns cover (probably involved in ~20% – 25% of all games) will have an effect. There is definitely scope for rerunning these numbers with/without Dublin and also in games completely excluding Dublin (or even Croke Park for that matter).

Note2; Control, and where it starts and ends, can be a very subjective thing. I tend to veer away from subjectivity – though to start to expand and add value I am going to have to dip my toe in that water (more of that anon) – however here I would estimate that ~98% of the time who is in control of a ball is obvious. The other 2%? I guess we’ll just have to go with it ….

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