Analysis of Manchester United's long ball strategy: Does the defence suffer?

Manchester United have resorted to using long balls many times this season

Perhaps a detailed statistical analysis of Louis van Gaal’s long ball football is not necessary – it is plain that the strategy has not worked this season. Manchester United’s performance against Tottenham Hotspur last Sunday may have been excellent, but the game saw United attempt a long ball 12.3% of the time* – the fourth highest figure this season. It is in this context that a study remains useful.

Opta defines a long ball as any pass longer than 25 meters. It is a neutral term and quite a few technical sides rack up a high long ball figure by attempting to play passes over the top. United boasts the second best long ball success rate in the top five European leagues, so the Reds are at least successfully hitting it long. Indeed, this analysis disregards accuracy as there is little variation from match-to-match.

With that said, United must produce results – and with Van Gaal’s side fourth in the Premier League it is hard to argue against his tactics. Only Chelsea, Manchester City and Arsenal have scored more than United in the Premier League while the Dutchman’s team boasts the third-best defence in the country. Correlation rarely implies causation, however.

[Technical note: at least one set of data needs to have an inherent trend – e.g. points earned by each team have an inherent trend of being directly related to team’s strength – built in for a high r squared value. Since long balls/shots/chances created by United in each game are essentially just a bunch of numbers independent to one another, r squared values are going to be rather low by definition. The theory behind r squared, however, guarantees that even a set of low r squared values may be useful in certain analysis.]

In Figure 1, below, there is a decent trend between chances created by United and proportion of long balls in total number of passes. The trend between shots attempted and proportion of long balls, however, is not as strong.

One argument, albeit speculative, could be that long balls lead to opportunities, but chances that are difficult to finish. After all, long balls help United gain territory in advanced areas, but the side is not blessed with the pace to chase these balls down. Nor do the Reds boast height in abundance.

Data Rant has already demonstrated that defence and attack are highly correlated. Figure 3, below, confirms the suspicion that United is a broken team this season. That is – there is no correlation between United’s offensive performance and defensive performance.

Does this mean that United’s defence is working, at least? After all, United boasts the third best defensive record in the Premier League this season. Figure 4, below, tells a slightly different story. The greater the proportion of long balls, more the chances created by opposition. In short, long balls have not been conducive to a sound defence – and David De Gea must be kept at all costs!

Intuitively, long balls, no matter how accurate, will allow the opposition some chance to organise a counter-attack. More alarming is the fact that there is a trend between shots conceded and the proportion of long balls.

That said, there is a counter-argument too. United’s average amount of possession is second only to Manchester City this season. Further, United boasts an average long ball completion rate of 57%, which is remarkably high. Whenever United concedes possession with a stray long ball the opposition is rarely in the right shape to mount a concerted effort at United’s goal. Rather, the opposition must rely on quick breaks. Jonny Evans and company have not been good at dealing with these breaks.

This observation is not news, of course, but the analysis that the agricultural approach could be at fault is fresh. The data paints a disturbing picture in which United is not converting long balls into shots and suffering defensively as a direct result. Causation is a bit fuzzy, but United’s data points to a broken team – and the direct approach is likely at fault.

Van Gaal’s side has enjoyed its best defensive games against Hull City, Stoke City, Leicester City, Sunderland and Tottenham – all at home. These games at Old Trafford also happen to be some of the best United attacking performances this season. The average proportion of long balls in these five matches was 8% – below the seasonal average of 9.9%.*

The five best offensive performances came against West Bromwich Albion away, and Chelsea, Crystal Palace and Sunderland – all at home. The average proportion of long balls in these five games was 7.2% – lower than the average in United’s best defensive games.

All of these games were played at Old Trafford. It is dangerous to draw any definitive conclusion from this observation, but these games do support the thesis that long balls are at fault for United being a broken this team this season.

Can Louis van Gaal find balance in Manchester United’s attack and defence?

Indeed, this analysis points to an obvious conclusion: Van Gaal needs to move away from a long ball strategy if only to fix United’s struggling defence. It might even restore the ‘balance’ to United that the Dutchman so desires.

After all, Tottenham had an off day on Sunday. United capitalised rather than forcing the North London club into submission – the Reds created just seven chances on 11 shots attempted. United will have to do better against Liverpool next weekend.

A brief note on methodology and data sources

1. Assumptions dictating linear regression have not been held strict
2. * Data sourced from Squawka, EPL Index and FourFourTwo Stats Zone – all Opta
3. * whoscored.com notes a far higher percentage of long balls, both against Tottenham and across the season – enetpulse