When Arsenal signed a 33-year-old Petr Cech back in 2015 it was always going to be a stopgap option, knowing that he wouldn’t have all that many years left for a top level club. Fast forward three years and despite recently giving him the number one shirt, Arsenal find themselves in need of a new long-term replacement for Cech, particularly after him having a sub-par season and showing signs of decline.
For this article I’ll try to find a new ‘keeper for Arsenal using StrataBet’s chance data for the xG models and, as a guide, Unai Emery’s PSG side for what’s expected in terms of distribution. I’ll be using an xG model that only takes into account shots on target and one that has the post-shot information about the chance. I’m pretty sure I’ve done something wrong in the post-shot xG model as very few teams under perform, for instance in the Serie A every single team over performs, so take the values with a pinch of salt.
Some good examples of pieces that use StrataBet’s ‘shot quality’ feature to look at post-shot xG include @BobbyGardiner’s two pieces on the Ringer, the first looking at Raheem Sterling and finishing while the second looks at David de Gea. Then @FinerMargins analysed La Liga goalkeepers using a post-shot xG model.
Why Do Arsenal Need A New Goalkeeper?
As previously noted, Cech is now 36-years-old and signs of decline seem to be showing. Interestingly however, his numbers seem to vary somewhat.
In the below embedded tweet @FinerMargins has him sightly out performing the expected goals against.
Premier League goalkeepers ranked by shot stopping this season.
— Ray Hamill (@FinerMargins) May 22, 2018
However, with the new StatsBomb data @YAMiAM9 had Cech concede the most goal above expected of all Premier League goalkeepers. I’d highly recommend reading about the new StatsBomb data and watching the presentations from the launch event, especially the goalkeeper presentation as it has a comparison of Cech and David de Gea this season.
In my numbers, using an xG model that only accounts for shots on target, Cech under performed by just 1%, which may not sound all that bad, but away from home he under performed by 16%. While this isn’t solely down the goalkeeper and more factors are at play, you’d assume this would be one of the reasons behind Arsenal’s away troubles this season.
Given Arsenal had a strong home record, more efficient defensive numbers away from home could have seen them at least compete for the top four.
Then, while Cech may be perform around the level of an average ‘keeper, I’d argue a top club should be looking at the goalkeeper position as a chance to gain an edge. Similar to something mentioned in the StatsBomb presentation linked above, clubs will happily spend big money on players who can perform efficiently in front of goal or even regularly out perform in front of goal, but a lot of clubs seems reluctant to do this for a goalkeeper.
Last season David de Gea conceded the same amount of expected goals as Petr Cech, yet De Gea ended the season having conceded 24 open play goals and Cech 43. Of course, it may not be just De Gea as there’s lot unaccounted for, but that’s 19 goals saved. Just think how valuable it could be to conceded 19 less goals across a season.
If Arsenal don’t have the resources to compete with the Manchester clubs, they need to find ways to gain an edge and a new ‘keeper could help them do that. I’d also claim Arsenal should be looking for a younger, more long-term option in goal as opposed to another stopgap option.
With this in mind, who are some candidates?
Jan Oblak – 25 – Atletico Madrid
Atletico’s Jan Oblak has been excellent as Atletico’s ‘keeper over recent seasons, regularly coming up with important saves, while at 25-years-old he’s only now entering his prime years.
This season Oblak has hugely out performed his numbers, his 35% over performance could only be bettered by David de Gea in Europe’s top five leagues this season. While his save percentage of 61.0% for shots within the danger zone (area the width of the 6 yard box and length of the 18 yard box) is a good portion above the 53.3% average and Cech’s 51.4%.
With his performances at Atletico putting him among the best goalkeepers in the world, there isn’t really any questions regarding his shot stopping ability, the main questions would refer to his distribution and availability.
Alphonse Areola, Emery’s first choice ‘keeper last season, went long the lowest amount of time in Europe’s top five leagues last season. The French goalkeeper went long just 17.9% of the time, whereas Oblak went long 70.6% of the time.
I’d imagine getting a ‘keeper to start rolling it out is something that be can be coached pretty quickly, it’s mostly if the manager wants a ‘keeper who can also play with his feet it becomes more of an issue. I’d say what Oblak can do with his hands would outweigh any problems involving the distribution with his feet, it’s just it’d be preferable to have a ‘keeper used to going short more often.
The other issue is that of availability. Oblak allegedly has a release clause of ~£88m, although he is supposed to be in contract talks as the club try to get this figure increased. However, this leads to two questions. Would Arsenal pay this price and would Oblak leave Atletico for Arsenal, or alternatively, would he pick Arsenal over the many clubs who’ll likely be sniffing around?
I’d lean towards no on both of those points, which pretty much rules Oblak out. I may be wrong and this may look stupid months from now, but I seriously doubt Arsenal would put up the money for him and if they did, I feel as though another club would be able to beat them to his signature. As great a goalkeeper as he is and as much as he’d improve Arsenal, I just can’t see him moving to North London.
Alisson – 25 – Roma
Alisson has had a great season for Roma and it’s no surprise several clubs are interested in signing him this summer.
@thefutebolist talked about Alisson in their piece discussing possible new ‘keepers for Liverpool, before I talked about him in my Liverpool piece from January. Alisson has kept up his impressive numbers from these pieces earlier in the season, over performing his on target xG conceded by 31%, behind only Oblak and De Gea in Europe’s top five leagues.
Then, while I’ve mentioned I’m sure I’ve done something wrong with this number, he over performed by 38% when taking into account post-shot information. Alisson also had a danger zone save percentage higher than that of Oblak’s, saving 64.9% of chances despite, on average, having slightly less players between the ball and goal than Oblak did last season.
Alisson also doesn’t go long as often as average, going long 40.7% of the time, while he also seems more than capable with his feet should Emery be looking for a ‘keeper who can help build from the back. The video of Alisson from my Liverpool piece can be seen below.
Thomas Strakosha – 23 – Lazio
Strakosha is another name I talked in my Liverpool piece from January and is another name that Arsenal should be considering.
At 23-years-old he’s incredibly young for a goalkeeper, but that hasn’t stopped him putting forward some impressive numbers this season. While he hasn’t put forward the mutant-like numbers of Oblak and De Gea, he over performed his on target xG conceded by 9% last season but this rose to 26% when taking into account the quality of the shot.
Interestingly his save percentage for shots within the danger zone is only marginally above average at 54.7% as it heavily fell off in the second half of the season. In the first of the season his danger zone save percentage was 67.7%, but just 42.4% in the second half of the season. While not encouraging, you do expect fluctuations in form from young players, while his xG performance is probably a better barometer than the save percentage.
Strakosha goes long slightly less than the 60% average at 57.8%, but he’s young enough where you’d think shorter distribution can definitely be coached into his game. While he does seem fairly comfortable receiving back passes and going short from the back. Below are just a few clips from a couple of games earlier in the season and while he’s no Ederon or Marc-Andre ter Stegen, you can see he seems comfortable offering himself as a passing option and building from the back.
Strakosha did sign a contract extension in October 2017 until 2022, so Lazio have no need to sell, but you’d imagine Strakosha would be much cheaper than Oblak and Alisson, then if he continue his development he may not be all that far away from their kind of numbers in 2/3 years time. It’s the kind of profile of player that it’d be nice to see Arsenal target, taking small risks on those under ~23 and performing at a high level, while still capable of improving further.
Alphonse Areola – 25 – PSG
Alphonse Areola may have made a couple of high profile errors for PSG in the past, but this season his numbers have been impressive.
He out performed his on target xG conceded by 11%, but taking into account the shot quality sees this jump to 28%. Add in a danger zone save percentage of 61.3% and it starts to paint an impressive picture.
As mentioned throughout the piece, Areola is also the ‘keeper who went long the lowest percentage of time last season and having played under him for two years, will have no problem with Emery’s demands. Recently Arsenal have shown a thing for signing players who have previously played for clubs their staff have worked at, with Sven Mislantat signing two ex-Dortmund players and being linked with plenty more, so why not continue that and go for Areola.
Areola may be more available than other options too. The Frenchman’s contract runs out in 2019 and if either PSG’s troubles with financial fair play or links with big-name ‘keepers are true, Areola could represent an opportunity to raise a bit of cash, particularly as they still have Kevin Trapp in reserve too. Adding to this, Newcastle are allegedly interested in Areola, while there were also reports PSG offered Areola + 5 million euros for Pepe Reina from Napoli a few months back.
Based on this seasons numbers Areola would be an upgrade on Cech, is a good age, familiar with Emery and could be available for a reasonable fee. He’s definitely an option I’d be looking into with all this in mind.
Roman Burki – 27 – Dortmund
Slightly older than the previous names, as he turns 28-years-old in November, Roman Burki has some good numbers for Dortmund this season and fits Arsenal’s recent recruitment policy.
Burki conceded ~5 more on target xG than Cech last season but ended with 4 less goals conceded than him. He outperformed his on target xG conceded by 19%, despite having a fairly average danger zone save percentage of 54.2%.
The Swiss goalkeeper also goes long lower than average at 39.2% of the time, so should be able to quickly adapt to Emery’s building from the back.
Burki is an interesting option, in @colintrainor’s post-shot xG model Romain Burki had marginally sub-par numbers in his first two seasons at Dortmund, before conceding less than expected last season.
He could represent a good option for Arsenal at a respectable price, but – even though he’s younger than a stopgap option – he doesn’t necessarily feel like the long-term answer for Arsenal between the sticks.
Koen Casteels – 25 – Wolfsburg
Another Bundesliga ‘keeper who has had an impressive season is Wolfsburg’s Koen Casteels.
The 25-year-old Belgian ‘keeper outperformed his on target xG by 10% last season and 13% when factoring in shot quality. His danger zone save percentage is above average at 56.5% and he represents a good age at 25, turning 26 in the summer.
He does go long more often at 57.3%, but again if it’s just going short that Emery wants as opposed to a ‘keeper comfortable with their feet, you’d imagine he’ll be able to adapt.
He did sign a contract extension last summer, with his new deal running until 2021, but with Wolfsburg having a poor season it’s plausible he’d be available for Arsenal – and Arsenal have even been linked with him in recent months. He definitely represents an option worth looking into further.
- Timo Horn – Performed around on par this season, but has been impressive for a few seasons in @colintrainor’s model, however he allegedly wants to stay at Koln after their relegation.
- Bernd Leno – Has been linked with Arsenal, has been 1% below par this season and under performed for six and a half seasons in @colintrainor’s model, so Arsenal should probably give him a miss.
- Jack Butland – Butland is reportedly available for £30m and out performed on target xG by 10% with Stoke last season. He does go long 84.7% of the time though, so would have some adapting to do to fit in at Arsenal.
Despite being one of the best goalkeepers in the Premier League for the last decade or so, Arsenal should be looking to replace Petr Cech this summer.
Jan Oblak and Alisson seem to be the two best options, however they don’t seem to be particularly realistic targets for Arsenal. It seems unlikely that Arsenal will pay the required fee for either of them, while it’s also likely other clubs should be in for them who can offer more than Arsenal at the minute.
The above is just a quick look at the numbers, and a lot more video would be needed before making any bold claims, but I’d lean towards Thomas Strakosha, Alphonse Areola and Koen Casteels being the best options to look into from above.
Strakosha is putting forward great numbers and has only recently turned 23-years-old, Areola also put forward some great numbers, worked with Emery before and could represent good value given he only has a year left on his deal, while, again, Casteels has some impressive numbers and will most likely be available given Wolfsburg’s disappointing season.
Arsenal have been linked with plenty of goalkeepers in recent weeks, so it’ll be interesting to follow what happens with their ‘keeper position over the summer.
This article was written with the aid of StrataData, which is property of Stratagem Technologies. StrataData powers the StrataBet Sports Trading Platform, in addition to StrataBet Premium Recommendations.