Football matches are a prime example of a complex system that changes dynamically throughout the 90 minutes of play. One team can dominate the match for a given period of time, controlling possession and playing in the opposition’s half of the pitch. But this domination of possession and territory is rarely constant for the entirety of the match, and is a fragile domination that often leaves the team vulnerable to counter-attacks by the opposition.
That is the reason why we have developed an Attacking Momentum plot that illustrates the dynamic flow of a match. The X Axis represents the time in the match, while Y Axis represents the direction in which each team is attacking. In the example below Manchester City are attacking towards the top of the chart and United towards the bottom, and the line in the middle being the half-way line. The coloured spikes represent where the team’s chain of possession ended on the length of the pitch, narrower peaks represent short chains of possession and similarly wider ones represent longer chains. The circles in the chart indicate shots by the team with the smaller coloured indicator circles indication whether the shot was on-target (green), off-target (red), hit the woodwork (yellow) and a star indicating that a goal was scored.
A great example of this plot’s effectiveness in illustrating the changes of momentum in a match is the recent Manchester derby, this was truly a cliche’ “game of two halves”. City dominated the first half, creating plenty of goalscoring chances, dominating possession and playing in United’s half. This domination meant that United had no shots at all in the first half and ultimately went into the changing rooms at half-time 2-0 down. The second half was an entirely different story, Mourinho’s men came out in the second half with something to prove. They took control of the match, and scored 3 goals by the 70th minute. This change in the match dynamics is clearly visible, in the first half City had more of the momentum illustrated by the high volume of light-blue peaks which were replaced by red peaks during Manchester United’s dominant period of the game and also highlighted as the only period of the match in which United had any shots on goal.
We can use this plot to better understand Roma’s surprising elimination of Barcelona from the Champions League in the quarter-final stage.
The first match between ended in a 4-1 victory to Barca who dominated the match in terms of shots on goal and Attacking Momentum. As is visible in the above figure, and expected at home in the Nou Camp, Barcelona enjoyed longer chains of possession and limited Roma to only 6 shots from open play. Adding salt to their wounds, Barcelona’s first 2 goals in the match came from Roma own goals through De Rossi and Manolas. Luckily for them, Roma’s late goal from Dzeko in the 80th minute gave them a lifeline in the tie, and ultimately proved to be crucial as they knocked the Blaugrana out in the second leg.
The second leg, shown above, was a completely different story. Roma completed the turnaround coming back from 3 goals down and going through on away goals, through an early goal from Dezko as well as De Rossi and Manolas scoring again, this time for their own team. As can be seen in the plot of the match, Roma had the majority of the Attacking Momentum in the match, they had longer chains of possession than Barcelona and created many goalscoring opportunities. Interestingly, Barcelona were limited to only 9 shots on goal and the majority of these shots came early in the first half or late in the second half, meaning that Roma very capably stopped Barca from playing their usual style of football. This is very impressive considering how dominant Barcelona have been in their domestic league this season, looking extremely likely to win the title in La Liga.
This is another plot that allows us to see the narrative of a football match swiftly and easily. There is little statistical evidence that momentum does exist in football, but regular spectators of the game will know that the 90 minutes of a football match are dynamic and the two teams trade periods of domination in a match. Using these plots we can now visualise this better than before as the Attacking Momentum plot allows us to see changes in the flow of football matches over time.
Data Scientist at Twelve Football