Scatter graphics: Championship, 2021-22
Now that the season is over (barring play-offs which I exclude for consistency), I can create final versions of the scatter graphics. These compare the attacking and defensive performances of every team in a division – each of the four graphics is explained briefly below and at length here.
First of all, here is how the number of shots taken by each club compares with those they face in return. The average number of shots taken per match is on the horizontal and the average number faced is on the vertical, so bottom right (take plenty, allow few in return) is good while top left (take few, allow plenty) is bad. The stripes are like contours: the greener the stripe, the better the performance (and vice versa for red).
Champions Fulham were the division’s most dominant side this season, taking almost two shots more than anyone else and allowing fewer in return than everyone except West Brom. The Baggies and nearby Coventry both created plenty of chances themselves, but we’re about to see why that wasn’t enough to sustain a promotion challenge.
Now let’s look at attacking alone. The horizontal axis stays the same as in the graphic above, but now the vertical shows the average number of shots needed to score each league goal. Therefore bottom right is good (taking lots of shots and needing fewer efforts to convert) and top left is bad:
While Coventry and West Brom took plenty of shots this season, they were among the division’s most wasteful finishers. Fulham were something else: not only were they the most frequent shooters but also the most clinical. Despite creating significantly fewer chances than the average team, Luton made the play-offs thanks a similarly ruthless streak in front of goal.
Next let’s look at the defensive situation – basically take the above chart and replace the word “taken” for “faced” on both axes. Now top left is good – facing fewer shots and able to soak up more per goal conceded – and bottom right is bad:
Huddersfield secured an impressive third-placed finish despite allowing opponents plenty of shots, thanks to repelling a high proportion of them. Fellow play-off qualifiers Nottingham Forest also saw their goal live a charmed life at times, with Millwall the only team to have soaked up more efforts per goal conceded. Birmingham meanwhile finished in the bottom half despite a fairly healthy balance of chances thanks to their porous defence.
Finally here’s an attempt at correcting the first graphic for the quality of chances created and allowed, using the same “expected goals” values that power my shot timelines (explained here). The reason for doing this is that the results tend to correlate more strongly with performance than when we treat all shots equally:
When we adjust for chance quality, Fulham‘s turbo-charged attack still sets them apart from the rest. West Brom looked good enough to finish in the top six overall – their poor luck in front of goal looks to have cost them this season. Interestingly, Huddersfield have again made the play-offs despite seemingly modest underlying performances – even more so than in 2016-17 when their defence looked a lot more solid.