Do promoted teams struggle to take chances?

Danny Graham excelled in the Championship, but has struggled for top-flight Swansea

Watching Shane Long miss a good chance to equalise for West Brom against Swansea on the weekend, it got me thinking – would he have scored an identical opportunity in the Championship?

You can extend the thinking to promoted teams; so often we see high-scoring Championship sides struggle to translate their strike rates into the Premier League.

But to what extent is this true? A recent piece by Decision Technology about Arsenal’s early season chance conversion problems shows how a fall in goal to shot ratio doesn’t necessarily mean a decline in an ability to score goals.

This is also true for 15 of the teams promoted to the Premier League since 2001, as shown in the chart below. A further 15 teams, however, showed enough wastefulness to suggest their ability to take chances had fallen significantly upon promotion; this is denoted by the yellow bars. Teams are sorted left to right, reverse chronologically by season of promotion.

Take Newcastle last season. Their Championship conversion rate was 16.5%, but fell to 12.7% in the Premier League. Given the number of shots and goals they achieved in the Premier League, there’s only a 1.6% chance that their true conversion rate was still 16.5%. This slim chance suggests their accuracy in front of goal fell upon promotion.

A final three teams – Blackpool, West Ham and Blackburn – all managed to increase their goal to shot ratios, no mean feat though statistically equal to their Championship rates.

Across all promoted sides though, it’s clear to see scoring goals is a tougher task in the top division, either because the chances created are of a lower quality or because of the pressure of greater scrutiny and stakes. Of course this isn’t necessarily a case of teams lacking Premier League experience, as many promoted clubs sign players with top-flight history. (Edit: as Tom notes in the comments, better goalkeepers make a difference – one of the things presumed equal when testing significance.)

It must be disheartening from Premier League new boys to consider that not only will they get fewer goalscoring opportunities in the top flight, they are also often less likely to take them.

That said there’s nothing to suggest losing your way in front of goal has an impact on your hopes of survival, where on the table below ‘worse conversion’ relates to teams with significantly worse goal to shot ratios.

The majority of teams since 2001 have beaten the drop, but through no obvious effect of maintaining conversion rates in front of goal. This somewhat supports the evidence that defensive records, and in particular clean sheets, are a better indicator of final league position than attacking figures.

There’s nothing for this season’s new boys to worry about yet either. Given their conversion rates last season and shots tally this season, there’s a 9% chance of Swansea and QPR scoring as many as 3 and 4 goals respectively, whilst there’s a 16% chance of Norwich scoring 5 goals or less, as they have done thus far.

So whilst you’d have expected all three of the teams to have scored more often based on their goal to shot ratios last season, it hasn’t fallen sufficiently to be deemed statistically significant.

It may not be entirely surprising that many promoted teams miss a greater proportion of chances in the top flight, but at the same time a lot of these clubs sign and bring up players with prolific Football League records. You might expect Danny Graham to have limited scoring opportunities in the Premier League, but frequently take the ones on offer, thus not greatly altering his conversion rate. So far, the opposite has been true, and the same can be said for many other players.

Whatever the reasons for missing more chances, promoted teams shouldn’t worry too much; it seems survival is more dependent on scoring at the right times and keeping it tight at the back.

Data from footstats.co.uk, who in turn get their data from football-data.co.uk. Shot figures and hence conversion rates may not match other data providers’ figures.