After the thrashing of Barcelona and Real Madrid there’s been a lot of discussion about the ascendancy of German football and the decline of Spanish football. But how surprising were these results and is there any chance the Spanish teams will be able to strike back?
Likelihood of First Leg Result
The first question relates to the unlikeliness of the result. Before the match was played the probability of Bayern Munich having a goal difference from the first leg greater than or equal to +3 was 8.9%. When we look at the probability of a +4 goal difference the probability is reduced to 2.7% but this is partly due to the generally low scoring nature of football. The chances of Dortmund finishing the first leg with a +3 goal difference was 8.3%. These results were not quite so unlikely as commentators have made out although the most likely result for both semi-finals would have been a 1-1 draw.
Despite conceeding the fastest goal in an El Clasico, Barcelona still triumphed 3-1 on Saturday. This drew them level with Real Madrid on points and ahead on the head-to-head rule.
But how important was this single match in terms of the chance of being top at the end of the season? To investigate I used the DecTech team strength model to simulate four scenarios: the chances each team had of winning the league before a ball was kicked on Saturday, plus the probabilities of taking the title after the Barca win, if the match had been a draw, and if Madrid had won instead.
This “six pointer” of a match is particularly interesting because Barcelona and Real Madrid dominate the league so thoroughly. At the end of August our model predicted one of these clubs would win the league with a chance of 99.5%. After this weekend’s games that figure is now in excess of 99.9%. The match’s importance is enhanced by the head-to-head rule which ranks teams on their record against each other if there is a tie on points, unlike the Premier League, which uses goal difference against all other clubs in the league. Continue reading →
We should cite some related work – Soccer By the Numbers used the variation in wins across teams to measure competitiveness, and 5 Added Minutes looked at points per game gained by top five and bottom five teams.
These analyses are worth a read. However, Spain doesn’t really stand out as an uncompetitive league using those rough measures since it’s only the top two teams who have extreme results (see our La Liga pre-season predictions). We used a different approach to highlight why Spain is different.
With the second week of fixtures in the Group Stages of the Champions League about to begin, we thought it would be interesting to look at how the structure of the competition affects the percentage chance each team has of winning the competition. What if the Champions League really was an, admittedly large, league of 32 teams?
Is the current format, including draws which are seeded and which force teams from the same nation to avoid each other until the Quarter-Finals a disadvantage for the smaller teams? Is this disadvantage more than offset by the nature of a knock-out competition allowing lesser teams to progress off the back of a couple of lucky performances?