Goalkeeper stats comparison

[rurikbird]

Something called xG, basically a system that rates every shot on goal by distance, which sector of the goal it was going into, etc, then produces a number for each goalkeeper whether their overperforming or underperforming their expected goal average. 100% means that that they are saving what they should be saving and letting in what they should be letting in; the top GKs are consistently above 100%. Here's a series of tweets from a stats guy who compared a bunch of goalkeepers with a special focus on Liverpool.

Now I see why we are reportedly considering Alisson, while the Butland lobby should surely be defeated. Karius is average, but Ming is even worse than I thought (at Liverpool):

 

[Dreambeliever]

Ming would surely be bottom

 

[darkstarexodus]

Would be interested in seeing this for De Gea, Courtois, Burland, Mignolet and a few others too. Very interesting.

 

[rurikbird]

Would be interested in seeing this for De Gea, Courtois, Burland, Mignolet and a few others too. Very interesting.

Sorry, I was adding bit by bit to the post and also apparently there is a limit of 5 tweets per post, so I had to break it up. Check below, all the names you’ve mentioned and more have been rated.

 

[rurikbird]

Part 2:

 

[rurikbird]

Part 3:

 

[rurikbird]

Part 4:

 

[rurikbird]

Part 5:

 

[Oncy]

Quantas never crashes.

 

[Frogfish]

Awesome work @rurikbird. Superb stat analysis too.

 

[Hansern]

You can see why our scouting team likes Allisson.

Butland should be a big N O.

 

[Insignificance]

You can see why our scouting team likes Allisson.

Butland should be a big N O.

That doesn' make sense as Allisson actually look decent. Our scouts would never spot decensy

 

[Hansern]

Our scouts have been very good for while now

 

[tombrown]

Our scouts have been very good for while now

I don't understand his comment about Mignolet and the difference a more compact defence makes in this stat. If the defence is more compact then wouldn't the xG be lower anyway?

 

[Modo]

Where are all the pundits who said that Guardiola was mad for binning Hart?

 

[rurikbird]

I don't understand his comment about Mignolet and the difference a more compact defence makes in this stat. If the defence is more compact then wouldn't the xG be lower anyway?

I think he's saying that team with a more compact defence, like Burnley, allow less high-quality chances (1 on 1s, uncontested shots, tap-ins etc) virtue of crowding their box and that's not really reflected in his metrics. So these stats tend to favor GKs from defensively-minded teams who face a lot of shots, many of which are not all that hard to save - like Mignolet in his pre-Liverpool days. This is also why I think Timo Horn playing for Cologne has a lot better stats than Bernd Leno, who is playing for attack-minded Bayer.

 

[Modo]

I think he's saying that team with a more compact defence, like Burnley, allow less high-quality chances (1 on 1s, uncontested shots, tap-ins etc) virtue of crowding their box and that's not really reflected in his metrics. So these stats tend to favor GKs from defensively-minded teams who face a lot of shots, many of which are not all that hard to save - like Mignolet in his pre-Liverpool days. This is also why I think Timo Horn playing for Cologne has a lot better stats than Bernd Leno, who is playing for attack-minded Bayer.

Kinda like how Reina looked behind Hyypiä, Carra, Agger and Skrtel. Throw in a DM or two as well.

 

[rurikbird]

I think the best use for these stats is to compare GKs who play for teams with similar style and stature. Like you can clearly see Neuer's quality, even though he plays for a team that attacks most of the time and concedes high-quality chances due to playing with a high defensive line. Courtois' numbers are a bit surprising, but I think it's correct - his best quality is the command of the area, not shot-stopping.

 

[Frogfish]

I don't understand his comment about Mignolet and the difference a more compact defence makes in this stat. If the defence is more compact then wouldn't the xG be lower anyway?

Yeah I noticed that too. The defence has nothing to do with the Xg which is purely 'expected to save' based on the section of the goal the ball is heading to, distance and the keeper's position etc.

 

[doctor_mac]

Interesting stats. I was admiring Heaton the other day. Interesting that his stats support he's a talented keeper. Obviously Oblak is the next big thing. If we could get him...well, I think we could achieve anything.

 

[KFC]

Interesting stats. I was admiring Heaton the other day. Interesting that his stats support he's a talented keeper. Obviously Oblak is the next big thing. If we could get him...well, I think we could achieve anything.

€100m Euro buyout clause, and we can have him

 

[doctor_mac]

€100m Euro buyout clause, and we can have him

Now that's the way to spend the Coutinho money!

 

[jason]

Oblak🙂

 

[Insignificance]

Where are all the pundits who said that Guardiola was mad for binning Hart?

When I said Hart was not good enough for top PL teams the ManWhoIsNeverRightNorHasAName rudicoul the statement...

 

[Modo]

When I said Hart was not good enough for top PL teams the ManWhoIsNeverRightNorHasAName rudicoul the statement...

Of course

 

[Woland]

Thanks for all these stats but work doesn't start again til Tuesday.

 

[jason]

/ Caps on.

 

[Brizzle]

Love these stats. It was a similar method someone had done on Danny Ward last season at Huddersfield that said despite their promotion, he was conceding more than stats suggested he should have been.

 

[Dirty Sanchez]

Stats are always interesting ~ nice work @rurikbird
There are of course many “non save related” factors missing in this evaluation though. Leadership, decision making , command of area, how he deals with crosses, and particularly distribution - where stats kinda end and scouts have to earn their money. How is Alisson at kicking/leg strength, or seeing and initiating quick counters from throws etc.

 

[darkstarexodus]

Fascinating stats. Many thanks for sharing.
Courtois is of course the big surprise in there.

Also very interesting to see Mignolets stats before and after joining us.