Friday, August 25, 2017

Some help to pick your defenders

Quick note: One of the reasons I restarted the blog this year was that my wife and I were expecting twins in late September so I knew I would be home a lot more with plenty of sleepless hours available to mindlessly consume football matches. Well, the twins didn't think this was a great idea and decided to convert xTwins into Twins on August 13th. This means I've been a bit delayed rolling out some of the models and ideas I had to kick off the season but once we get into a routine I will ramp up the content a bit. I like to think that they are already concerned about the potential issues around small sample sizes and wanted to force me to wait until the season was a few weeks old before overreacting.

Selecting defenders and 'keepers requires a different strategy to your attacking options, given that so much of their value is locked up in their team's performance. Of course, playing on a good team will help any player but while it's possible to have a lot of success as a forward or midfielder on a mediocre team, it's really hard to do so as a defender, barring a freaky season where you get extremely lucky with goal conversion or are fortunate enough to be played higher up the pitch.

Thus, with a few exceptions over the years, I tend to pick the team first and then figure out who offers the best way to access that unit. This will require a weighting of three factors:

  • playing time
  • price, and
  • attacking threat

Generally you will want to ensure the playing time factor first and then weigh the attacking threat against price tag and see how much bang for your buck you can get. Hopefully the below viz allows this to be done quickly for each team. Let's run few a couple of teams below to get an idea of how I hope it might work.

Note: The data within is based on the 2017-18 season only and thus needs to be taken with all the relevant small sample warnings. If you have a significantly higher or lower opinion of a player's attacking ability then don't totally discount it, but this might serve to adjust your prior, especially once we get another week or two under our proverbial belts


Brighton
Let's start with an easy - if somewhat theoretical - example. I must concede here that I haven't seen Brighton play a full game this season so this is a theoretical pick for illustrative purposes. Chris Hughton has picked a consistent back four in the first two games, all of whom cost 4.5m so if you wanted a Brighton defender you should simply be looking to maximise attacking threat, which to date points to Lewis Dunk by a reasonable distance. Suttner's 11 passes in the final 3rd point towards a player who might create chances in the future but otherwise the pick here should be Dunk. If these numbers hold up then it would start to suggest that holding other Brighton players would be a mistake.

Southampton
The first thing to note here is that Bertrand comes at a premium to his teammates yet, at least so far this season, actually has a lower attacking threat than both Cedric and Yoshida. Now, in this particular case I think one might want to exercise a bit of caution as Bertrand has a decent history of delivering solid attacking returns, but if this trend continues then it makes little sense to own the former Chelsea man. The data would suggest that Yoshida is an interesting differentiating option as he's provided the same attacking threat as Cedric but is owned by just 2% of managers compared to Cedric's 12%.

Chelsea
David Luiz's performance last week in midfield received good reviews which makes him well placed to earn minutes in this team. At just 6.0m he brings with him a good attacking threat which in theory then renders Cahill, Azpilicueta and Rudiger as poor investments. The question then becomes how much better Alonso is and whether that gap justifies the extra 1.0m. If you are aiming for a 2,200 point season then that 1.0m will need to earn you somewhere in the vicinity of 22 points (this gets more complicated later in the year, but bear with me for now) which is a goal and a handful of assists or 3-4 goals. That's a fairly significant haul and so while every else dives on Alonso after last week's heroics, I would suggest that the decision is closer than it looks.

With just two gameweeks in the bag, it's hard for players to really start to distinguish themselves from their teammates but I hope this little viz will be useful in the coming weeks as you look to structure your defense, perhaps during a wildcard international break.

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