Analysing goalkeepers part 2: EFL Championship, Leagues 1 and 2

Goalkeeper data analysis part 2

Following on from my previous article on using data to analyse goalkeepers in the EPL I said I would do the same for the keepers in the last of the three EFL leagues, so as promised here we go!

SkyBet Championship

Now im not going to go into all of the detail of the metrics published in my previous post as I think we all had a fair bit to read in that post so if you need a refresher I suggest you screenshot the methods and refer back.

So for the three leagues I will be showing the following-

  • Save percentage
  • AAGS (above average goals saved)
  • xGA (expected goals against)
  • adjsve% (adjusted save percentage)
  • I wont be adding in some of the other metrics like-
    • Distribution
      Coming off line
      Throws

    This is purely because I am basically then doing a lot of other peoples work for them and they would have a decent set of numbers to work from but also I have people who are relying on me for a complete set of the information above and to share all what I have wouldnt be fair on them either.

    All of the tables ahown here are based on the 6 games played so far.

    So lets start with what most pundits, analysts, players and managers probably consider the toughest league to get out of, the infamous SkyBet Championship.

    Championship save percentages

    You dont need me to tell you that Middlesbrough’s Darren Randolph has started the season in exceptional form in between the sticks for Tony Pulis’ team.

    Boro’s No.1 Darren Randolph

    Having faced 20 shots on target so far the former West Ham keeper has managed to save a whopping 18 of them and only conceding on 2 occasions hence the excellent 90% save percentage. A stat that will be backed up furthermore in the next table.

    A keeper, more importantly a young keeper, that has really caught my eye is Leeds United’s Bailey Peacock-Farrell. The 6′ 4″ 21 year old joined Leeds after being released by Middlesbrough in 2013 after spending 7 years on Teeside in the academy.

    Peacock-Farrell looks to have a bright future and under goalkeeping coach Marcos Abad, who previously worked under Aitor Karanka at Middlesbrough, he has an excellent tutor. Shot stopping (18 saves out of 22 faced) is another good record to rival Randolph’s.

    Two positive features of his game I have noticed is firstly his ability to be able to read what could happen infront of him in regards to coming off of his line quickly for a big lad and secondly his willingness to come for practically every cross into the box. An impressive start from the Northern Ireland international.

    As I alluded to earlier Randolph continues to impress in this AAGS table. Having directly saved Boro of nearly 5 goals, an excellent tally indeed.

    Mulder, Dawson, Camp and Archer of Swansea, Sheffield Wednesday, Birmingham City and Millwall respectively all boast decent records as well so far. As of course does the aforementioned Peacock-Farrell.

    Keepers in the bottom five of the table are maybe a tad hard done by as we must take into account the defensive capabilities of the players in front of them as of course we should for the keepers at the top having a decent defence in front of them, however being responsible for nearly 4 of the 9 goals your team has conceded doesnt make for good reading.

    Dean Henderson has adapted well to life at Sheffield United as has Sam Johnstone at West Brom. Early days but there are some very good goalkeepers in the Championship and their needs to be.

    SkyBet League 1

    For me this is where things get interesting. Can we find a keeper in theses type of leagues that would be capable of making a step up in class.

    Posh’s Aaron Chapman

    Peterborough United’s 6′ 4″ keeper Aaron Chapman has come to the fore after signing for The Posh in May of this year from Accrington Stanley. 28 year old Chapman has had some serious injury issues in the past but has been a shining light for Steve Evans’ side in their top of the table start to the season and with a AAGS of 7.57 he really has won his side some games already with a save percentage of 83% as having faced 30 shots and only conceding 5 goals (with an xGA of 12.51) it will be interesting to see if he can keep this kind of form up. A tall keeper who likes to come for crosses is also always a bonus.

    Another impressive keeper is Pompey’s Harrogate born Craig MacGillivray.

    Saving 19 shots of 23 faced and conceding just 3 goals with an xGA of 9.75 is another excellent return for the south coast side. After making ninety appearances for Harrogate Town MacGillivray signed a two year deal with Walsall in 2014 and then went on to play for Shrewsbury on a one year deal before joining Portsmouth in June of this year.

    I have watched him on several occasions and I have been very impressed with his decision making on coming off his line quickly and also his positioning and his stand- up-as-long-as-possible attitude when facing a one on one situation.

    He is good enough to be playing in the Championship in my opinion.

    Walsall’s Liam Roberts is another keeper I like and at only 23 he hopefully has a good future after a spending a lot of time out on loan in the Vanarama conferences in recent seasons.

    SkyBet League 2

    Topping the league at this moment in time the Cowley brothers Lincoln City team have made an excellent start to life in League 2 after gaining promotion on winning the National League title last season. A key player in the side is goalkeeper Grant Smith. The former Reading and Fulham youth team player joined Brighton’s development squad in 2012 but was released in 2014 and spells with Hayes (twice) and more recently Boreham Wood. Smith joined The Imps in June of this year and looks to have started very well indeed.

    Lincoln keeper Grant Smith

    With an AAGS ratio of 5.37 and conceding only twice with an xGA of 7.37 the early signs are good.

    Yeovil Towns on loan Chelsea keeper Nathan Baxter is also a very exciting prospect. The 6′ 3″ 19 year old has been with Chelsea since 2006 when he was 9 years old and he his thought very highly of at Cobham so I am told. Loan spells at the Met Police, Solihull Moors and Woking have helped him ease into senior football and then into League football with Yeovil.

    These early numbers that Baxter has produced are testament to his confidence in his goalkeeping ability. Having faced 20 shots conceding just 3 goals with an xGA of 8.01 is impressive for any keeper let alone a lad his age. Being responsible for keeping out 5.01 goals so far this season is credible indeed.

    In summary

    I hope these metrics and methods have been as enjoyable to read and decipher as they were for me when compiling them.

    I havent covered the National League purely for current on going reasons although I have compiled lists and so forth for it.

    Any questions do give me a shout on Twitter

    @ThatGarateyjc

    or on my LinkedIn page

    http://linkedin.com/in/gareth-cooper-b78502136

    Thanks for reading.

    Gareth Cooper

    GC Analytics

    Goalkeepers in the EPL: Using stats and data to measure goalkeepers in English football

    Liverpool keeper Alisson

    For the player scouting I get asked to do not a huge amount of it involves looking for goalkeepers.

    Nothing unusual about that you might say considering there are far more outfield players to look at than the man between the sticks.

    When clubs are looking to sign a new keeper it requires specific scouting methods to go alongside more traditional ways of looking at his/her performances. Looking at some data and stats and then applying them to some familiar and maybe unfamiliar metrics can give a better understanding of what a certain club is looking for in a new No.1.

    The Importance of Adaptation

    An easy example to use is of course Is Ederson at Manchester City.

    Ederson: City’s £35m capture from Benfica

    Whether a keeper can adapt to a teams playing style is a big factor when recruiting.

    Ederson has excellent distribution from not only his feet but also his hands , he has good shot stopping ability, his starting positions are excellent when preparing to come for crosses and on other set pieces, and that’s before we delve into his superb long ball delivery and eagerness to always be on the front foot to start counter attacks.

    So what can we use to back up what video scouting is showing us?


    Crosses

    Depending on what you want from a keeper varies on what metrics we want to apply to get an outcome that would show us a baseline and a rough idea for which keeper would look into more and compare some video to.

    A question we could ask of a goalkeeper that would be useful to look at if we were a team keen on using counter attacks or getting the ball moving ASAP would be- does he tend to come for crosses quite often?

    EPL catch success so far 18/19

    Above is a graphic detailing the crosses faced by keepers in the EPL and not only their catch success rates but also added in is whether we can identify any trends in whether they tend to punch the ball or prefer to catch it.

    Now with all this we must bear in mind the fact that at the time of writing their has only been 4 EPL games so to make a comparison at this point in a season is pretty impossible but we are looking at how these can be applied and the longevity of the metrics. This is one of the reasons why I like to include the three other English leagues as we have a bit more of a sample size and the other is because we may find a keeper that could make a step up. This I will be covering the findings from in a post in the days following this one.

    Back to the graphic and crosses and maybe predictably we can see Ederson is an early front runner. Even on last seasons evidence its clear the City No.1 likes to catch rather than punch, and for a reason, he catches to start counter attacks from short throws or his excellent, accurate long ball kicking ability.

    Hugo Lloris is much the same but a surprising inclusion is Watford’s Ben Foster. The Hornets unbeaten start to the season is testament to a keeper than has had his ups and downs over the years but overall is a reasonably consistent goalkeeper. Having faced 22 crosses and successfully catching half isnt bad going but is probably expected.

    Looking at some keepers, could be backed up by the following, throws?.

    Choosing to throw the ball rather than lump it upfield is another sign of a team liking to play out from the back and building from throws from their keeper to a defender and this is useful when compiling opposition reports. Again Ederson is up near the top of the list but we would expect this anyway again given the style of play. Fabianski is another who tends to release the ball early but in a odd trend we see Foster at the bottom of the list possibly suggesting Watford prefer him to look long for Deeney and co. The same applies to Cardiff, Huddersfield and Brighton all long ball teams so even at an early stage of the season we can maybe identify a small trend here.

    On the front foot

    The trend of a sweeper keeper is more prevelant nowadays and teams are looking more and more for a keeper that is good with his feet but also willing to come off his line to deal with balls played in behind their defence.

    Once more Watford’s Foster shows another quality some teams may look for. Remember these are small samples but its another valid point that Foster is happy to tidy up and come out of his area to clear up loose through balls and such like.

    The importance of shot stopping

    A blindingly obvious important area of goalkeeping is shot stopping so can we work out from some data how good a keeeper is in this area and if so how much has he helped his team in winning/losing/drawing games along the way?

    Inspired by the excellent work of data scientist Derek Yam (@YAMiAM18) I have compiled the graphic above on measuring a keepers shot stopping ability.

    The method

    Adjusted save percentage is a method that shows us a level in regards to if a keeper is performing better or worse than the average keeper in the league we can calculate this by showing the difference between expected goals against (xGA) and the actual goals conceded and then dividing by the total shots on target.

    Another metric that can be used is Above Average Goals Saved which is an estimate that shows if a keeper has directly cost their team goals and vice versa. This is basically calculated by using the difference of the expected goals against divided by goals conceded.

    Derek’s work is exceptional in this field and has personally opened my eyes to some very accurate ways of looking at goalkeeping metrics.

    The results

    A minus figure on the AAGS tells us that a keeper has directly cost his team that many goals for example we can see that Petr Cech has been responsible for letting in 1.27 of Arsenal’s goals so far this season but he has faced 27 shots conceding 8 goals with an xGA of 6.73 hence the -1.27 number so we can argue either way in terms of good or bad (yes i know its only been 4 games but this is just to show the reasoning at this point) on the flip side of that we have Spurs’ Hugo Lloris who has kept out 2.64 goals with an xGA of 4.64 and facing only 10 shots and even at this early stage this is considered a good return.

    In summary

    Their will always be doubters around that will say whether or not it is fair and and also how to measure a goalkeeper when it comes to using data but I hope I have shown, with the help of others of course, that their are ways of using these kind of metrics to evaluate and come to a conclusion alongside more traditional scouting methods (of which i have experience of both in a professional setting, trust me it works).

    So far this year already i have been impressed with Alex McCarthy and Ben Foster and although these methods are by far worth much more over a longer period of time they are still a one way of finding out which type of keeper would suit your team and there are more than the metrics and stats I have mentioned that we can use to evaluate a goalkeeper.

    As I mentioned before, I will be publishing a quick article and some tables on the keepers in the Championship and Leagues 1 & 2 in the days following this one.

    Gareth Cooper

    GC Analytics