xGunners: Burnley defy xG to propel up the table

Burnley currently sit tied on points in 5th place, even with Arsenal and Liverpool. They are one point out of fourth and the Champions League places. I defy you to find any pundit who predicted their fast start. So how are they doing it?

Burnley have done it mostly with defense; they’ve allowed just 8 non-penalty goals this season. That’s 4th best in the league, even with Chelsea. Based on the xG allowed numbers,they are allowing significantly less goals than expected this season. In xG allowed they drop from 4th in actual goals all the way to 14th in expected goals this season with 15.8 xG allowed.

Looking at how improbable it is to over perform xG allowed by over 50%, I have used the longterm expected goals simulator created by Danny Page to calculate the odds of only conceding eight goals this season based on the shots that they have allowed.

Danny Page, Longterm expected goals simulator

Based on this simulation conceding 8 goals should happened just 22 times in 10,000 simulations (0.22%).

One possible explanation for the disparity between actual and expected is shot blocking. Burnley are second in the league in block percentage at 37%. The blocks that they made this season have been worth 3.5 xG. That gets us closer to the expected goals number, but still has them over performing their xG allowed by four goals. Again, we can look at the longterm expected goals simulation to see how this the probability of this outcome:

Danny Page, Longterm expected goals simulatoe

The 8 goals they have conceded now happens in 160 of 10,000 (1.6%) of simulations. Their current season is still an outlier but now not quite as extreme as before. The only explanation left is looking at happens to the shots that weren’t blocked but did get on target.

Obviously when a shot is taken three things can happen, it can be blocked or it can get through and be a shot on target or completely miss. We’ve already looked at blocked shots…so now we turn to the shots that aren’t blocked.

Against Burnley, opposing shooters they are less accurate than the league average (40.8% compared to 44%) and against Burnley, the shots that are finding their way on target are being saved at a very high rate. This season Burnley as a team has the 3rd best save percentage behind only David DeGea and Thibaut Courtois, saving 83.7% of shots on target.

While Burnley keepers are saving just about everything that is coming his way, expecting this to continue is probably not a good bet. The research suggests that this is where Burnley fans should start to worry – save percentage is not something that reliably persists for most goal keepers. At some point, Burnley keepers should regress back towards the league average between 65% to 70% save percentage.

A caveat, there may be things not captured in the regular data that may be repeatable. Burnley are very good at pressuring shooters. According to Stratabet data (which ranks defensive pressure for each shot on a scale from 0 to 5) Burnley average a 2.4 pressure-level for each shot against compared to the league average of 2.1. This mark is 3rd best in the league behind Chelsea and Tottenham.

Burnley are also good at clogging shooting lanes. They average 3.1 defenders between the shooter and the goal compared to the league average of 2.6, which is tied for the best mark with Brighton.

Burnley’s defense has been improbably good so far this year and has them in unprecedented heights in the table. Burnley are putting up on of the 1 out of 100 situations where this can happen. They’ve been especially good at blocking shots and putting pressure on shooters. Arsenal should expect the 18 yard box congestion and shot blocking to continue, but Burnely keeper performances shouldn’t be relied upon to continue forever and should come back to Earth sometime. Let’s hope it starts on Sunday against Arsenal.

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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.

Burnley xG against data

-Updates made to reflect that Nick Pope and Tom Heaton have both made starts for Burnley, the previous version of this post failed to mention Pope and attributed all the good performances to Heaton. I apologize for this mistake.