Expected goals: What does the data say about Manchester United’s invincibility at Old Trafford?
Manchester United are undefeated in their last 22 English Premier League home games and have kept a clean sheet in each of their 5 home league games played in the current campaign. In fact, Lloyd Dyer is the only visiting player to score at Old Trafford this season, pouncing on some poor mishandling from 21-year-old substitute goalkeeper Joel Castro Pereira in the dying moments of Burton Albion’s 4-1 Carabao Cup defeat to the Red Devils, to earn a late consolation goal for the visitors.
In the only other 2 games played at ‘The Theatre of Dreams’ this season, neither Basel nor Benfica could breach the United rearguard, with both sides failing to score in Champions League group games.
United look to be in good shape to make it 6 clean sheets from 6 home games in GW12 as well, judging by the latest Premier League team goals projections which are calculated by converting the latest betting odds into goal expectancies.
But have they been lucky to record 5 successive home clean sheets in the Premier League and just how impenetrable is that defence?
Well, one way to measure it is to look at one of the new metrics that is getting more and more exposure in mainstream media – xG which stands for expected goals. This puts a value on every scoring opportunity created in a match and uses historical records to determine the probability of it being scored. So, for example, if penalty kicks are scored 76% of the time, they would have an xG of 0.76.
There are a number of resources providing this sort of data, one of which is Understat, so it’s possible to see how many goals a team should have scored as well as the number they would have been expected to concede based on the chances they and their opposition created on the day.
So far at Old Trafford in the 2017/18 Premier League season, United have a goal difference of 15-0 but their xG and xGA (expected goals against) figures read 13.18 and 3.69 respectively. This suggests that they have been somewhat fortunate to secure those clean sheets but no doubt the brilliance of David De Gea will have played its part.
Having a top quality goalkeeper who is capable of pulling off saves that the average shot-stopper might not is obviously an advantage but wasteful finishing is just as likely to be the route cause. That is something that may concern fans of Newcastle United, the side that has the unenviable task of breaching the United rearguard in GW12.
José Mourinho has built the foundation of his sides on solid defensive lines throughout his career, so these stats are not all that surprising. However, what is astonishing though, is the fact that Liverpool currently have a better ‘home’ xG than United and the rest of the division for that matter. This is quite remarkable for a team that has conceded more road goals (16) than any other side in the Premier League this season. Talk about chalk and cheese!
Perhaps this will make the pundits that like to stick the boot into the Reds’ defensive frailties on a regular basis finally cut them some slack. Don’t bank on it though!
They have only conceded once at Anfield in the league and it’s also worth pointing out that they have improved at restricting the number of opportunities they are giving to visiting sides as the season has progressed. This is reflected in their xGA figures of 0.73, 0.48, 0.33, 0.24 and 0.06 for the visits of Crystal Palace, Arsenal, Burnley, the aforementioned United and Huddersfield Town, with the Terriers being the latest side to visit Anfield.
Next up for the Reds are the Saints, a side that have really struggled to convert scoring chances, so the prospects of another Liverpool clean sheet look very favourable.
Sticking with players from sides that make their home a fortress is an appealing thought for many Fantasy Premier League managers – be warned though – Newcastle and Southampton will be looking to pinpoint any cracks in those fortifications in Gameweek 12!