Five games into the season, we’re yet to see a goalless draw in the WSL. So how are each club looking in defence and attack? Which clubs look good to target for captaincies, and which underperformers could come good? Let’s take a look through the lens of expected goals.
Expected Goals
Expected goals (xG) is a “statistical measurement of the quality of goalscoring chances and the likelihood of them being scored” [Goal.com]. Expected goals against (xGA) is the reverse; a measurement of the quality and amount of the chances a team is conceding to the opposition.
If a team is consistently scoring more than their xG, it might suggest that their results are based on less sustainable factors, like luck or exceptional finishing. Likewise, if a team is conceding fewer goals than their xGA suggests, they could be being bailed out by exceptional defending or their opponent’s poor finishing.
Below, we’ve plotted the WSL clubs’ expected xG and xGA. You can see Chelsea stick out as the best performers in defence and attack. At the opposite end of the scale, Leicester’s poor defence is by far the worst, conceding the most xG in the league.
The state of the middle cluster of clubs will be unsurprising to many managers. Arsenal, Spurs and Brighton come across as good defensive performers. Man United, while not so defensively strong, have a creative attack in terms of xG, second only to Chelsea.
Reading and Birmingham, sitting at the bottom of the league table with Leicester, don’t cover themselves in glory, conceding more chances than average and creating less than 1 xG per game.
Overperformers and Underperformers
Naturally, xG doesn’t perfectly match the reality on the pitch, especially over only 5 games. However, it is still useful to us as fantasy managers, helping us to see which teams are overperforming or underperforming compared to their expected results.
For example, this chart plots teams’ total xGA against GA. The dashed line is where x=y – in other words, when xGA perfectly matches actual GA. To the left of the line, teams concede more goals than expected; to the right, they concede fewer goals than expected.
We can see Arsenal and Spurs have conceded marginally fewer goals than expected this season. Brighton’s solid defence is performing as expected. West Ham are also conceding fewer than expected, as are, quite shockingly, Leicester City. Several teams are underperforming defensively relative to xGA, including Chelsea, whose premium picks are ever popular with ShePlays managers.
Meanwhile, in attack, Arsenal are vastly outscoring their xG. Most other teams are pretty much performing as expected, being clustered close to our reference line. Chelsea’s strong xG is being more than matched with goal returns. Brighton, helped by Kaagman’s penalties, also exceed their xG.
How sustainable is it for clubs to regularly outperform or underperform compared to xG like this? Looking at the same charts for last season, we can see that clubs actually tend to perform pretty close to their expected figures over a whole season. The only notable exceptions last term were relegated Bristol City’s poor defence and the strong finishing of Everton and the top 3 teams.
Attack and Defence Points
xG and xGA can help us identify the teams that are full of goals, or which seem likely to bag us clean sheets. However, attack and defence points are a really important part of the ShePlays game that we can’t ignore.
The chart below plots clubs’ attack points against their defence points. We can see that some clubs are taking actions during games that create fantasy points value without necessarily rescuing their teams’ xG and xGA.
For example, Leicester and Reading players, whose teams both register poor xGA stats, have some of the highest defence points in the game. Meanwhile, Man City still have a good showing for attack points, despite not being a standout team for xG.
Most promising for fantasy managers, some teams, like Arsenal, Chelsea, and Spurs, are racking up the bonus points while also impressing with their goals and underlying xG. This certainly adds to the case for picking players from these teams.
Final Say
You can draw your own conclusions, but I think these are some of the main points for fantasy managers to take away:
1. Keeping an eye on xGA is a good idea. Based on last season, in the long run, good defences are likely to come good. Your defenders who are only shipping a few more goals than expected, like Chelsea, could well be worth holding long-term. Reverting to their expected GA would mean picking up valuable clean sheet points. And generally speaking, solid defences can help your players’ GD points tick along.
2. Teams like Spurs and Brighton have impressed so far and are performing near enough to their xG. Their assets should be regarded as serious prospects, not flashes in the pan.
3. Arsenal’s amazing goalscoring form is slightly deceptive. They’ll still probably wind up near the top of the goalscoring charts, but I wouldn’t go all in on them. Chelsea look the best team going forward based on xG and their strikers can’t be overlooked.
4. There’s great value in attack and defence points! Goals and clean sheets (xG and xGA) are not the be all and end all of the game. Players from poorer teams can rack up bonus points, while players from title contenders might be bringing even more to your team through the magic of bonus points.
Good luck, managers, and keep watching the xG!