“The scoreboard is the only stat that matters”
So how do you score points in rugby?
Traditionally, of course we’d use a combination of the scoreboard and the “eye test” to measure how good a team is in attack. Recently however, with data and analytics becoming increasingly popular in rugby, stats such as “number of 22m entries” (Creating Opportunities) and “Points/22 entry” (Taking Opportunities) have been used to measure the above. Of course the opposite applies to the defence.
Beyond this, others, including BF Sports Analysis have sought to create alternative interesting metrics with linebreaks per possession stats with Super Rugby Teams.
“number of linebreaks” (creating opportunities) and
“linebreak conversion to tries” (taking opportunities).
As with all measurements, there are limits to the application of these metrics; Japan for example like to run out of their own 22m a lot and therefore create a lot of linebreaks (7 against the British and Irish Lions for example). However it is naturally more difficult to finish those linebreaks than those created further up the pitch (Japan converted none of those linebreaks, instead scoring their try from maul peel 5m out).
Of course there is more to rugby than linebreaks and 22m entries and other stats that do effect the creation of opportunities include winning collisions, having good exits, gainline success, having the upper hand at set piece and conceding less penalties and many more.
Measuring Scoring Efficiency in Other Sports
Other sports have begun to develop similar methods to measure attack proficiency. For example, Basketball uses Offensive/Defensive Rating, Ice Hockey and soccer using xG (expected Goals) as a means by which to measure both creation and/or scoring efficiency. At BF Sports Analysis, we have also developed an “Expected Points” model or xP to measure both creation and execution.
What is Rugby xP?
BF Sports Analysis uses a database of tens of thousands possessions in rugby to compare efficiency against. This database includes games from the 6 nations since 2020, Super Rugby Aotearoa 2020, All Ireland League games, National 1 (England) games, German Bundesliga games and so on. We have a database for the women’s game as well.
For example, our xP data has the ability to compare your points scoring efficiency from a 5m lineout to that of the average team in that position.
Our xP system focuses on team strengths and efficiencies rather than individual contribution. Basketball who are far further ahead in analytics are still playing around with this as to who to attribute the value of winning a defensive rebound too for example – what % is the shooter missing, the on the ball defender, the guy who grabs the rebound and the other players who have boxed out the shooting team. It evidently is different per each shot and do you work on an averaging method which would require a larger database to be accurate or do you try to individually account for each rebound (time consuming) or do you just give the box score of who got the rebound?
6 Nations xP
Using the above measurements of BF Sports Analysis xP, we can identify which teams are scoring more efficiently and from which possessions. But firstly, lets look at the some of the more well known measurements.
Given that Ireland played 60 minutes against a 13 man Italy, their stats on these fronts greatly inflated, In order to account for this advantage, we have included both Irelands attack proficiencies with and without the Italy game to give a more rounded idea of how well their attack is actually firing.
It is no surprise to see France leading and for the most part on these charts.
Scotland interestingly, created the least amount of 22m entries per match so far. Wales’ inefficiency at converting entries and linebreaks to points is another standout point.
Teams who play like England who are reluctant to attack from deep typically have a higher conversion rate from linebreaks. This interestingly contrasts with the aforementioned Japan whom a certain Eddie Jones used to coach.
BF Sports Analysis xP here allows us to see who is efficient at converting possessions in to points. As both stats are worked from points scored as a variable, there is no surprise that there is a linear correlation (R^2 = 0.71). Scotland are the team furthest from a the line of best fit which is where we’ll look first.
Hence, Scotland fit into a team not creating opportunities in this xP model. This fits well with Scotland having the least Opposition 22m Attacking Entries.
One likely factor in this is Scotland’s discipline giving away the most penalties per match with 12.7. 5 of those are occurring in attack per match which is them giving up a turnover and also a loss of normally territory or points.
Scotland are the team most content to play from deep. Only kicking on 48 of their 103 possessions starting in their own half (47%). With them playing from deep, 10 of their 15 attacking penalties have occured on possessions that start in their own half. 2 of those 10 penalties had a linebreak preceding the penalty.
Scotland’s 6 possessions / breakdown turnover or penalty particularly standing out in our database.
On the positive side for the Scots, they have the best lineout in the competition winning 97.7% vs the competition average of 90% this season. This is likely to be a contributor to their positive xP and efficiency in scoring from lineouts which sits at 13.1 points more than an average team would expect to score from lineouts given how many and they’ve had them.
This has put a spot light in Scotland’s inability to progress up the field as a potential cause for concern.
England's Scoring Inefficiency
England, interestingly, are on the opposite side of the fence to Scotland, creating chances by having high value possessions but not turning it into points.
With England’s heavier kick strategy they are often not attempting to score from deep hence they lose efficiency in scoring from that point of view.
By kicking more England engage in more kick tennis and means they have had more possessions per game than Scotland, 8 more specifically, although they still trail behind Ireland and France in that regard.
England will look back at their relatively low opposition 22m possessions and linebreaks/game and linebreaks/possessions as possible reasons for this.
One of the advantages of England’s kick heavy strategy is the avoidance of errors. England have the least amount of penalties against in attack (see penalty figure above) and have the least breakdown turnovers/possession (11.7). Taking away from England’s good discipline in their attack is their indiscipline in defence, conceding 8 penalties on average in defence.
For England’s strategy to create opportunities, they need a high kick regain % to gain their opportunities and territory. They are 2nd in regaining kicks behind Wales’ impressive 41% although it is a smaller part of Wales’ game plan with just over 7 contestables kicked per game, making England the only team who are more successful than average who do it more than average.
Italy interestingly, who kick the most contestables per match have the worst return at 25%.
With England, those contestables have resulted in a try directly – after a double regain for Kyle Sinkler’s try vs Italy. The high regains % is resulting in England having those valuable possessions but their ability to be efficient in scoring afterwards might make them questions their risk/reward approach to attack.
The beautiful thing about rugby is how there are so many different ways to win a rugby match evidently as shown above. France and England’s territory focused strategies are yielding the best and an average return respectively, Scotland’s higher possession focus has provided mixed results and Ireland’s extraordinary discipline has been paying dividend for them.
Style's Make Fights
The fascinating element of the 6 nations is how teams evolve through out the tournament; will Wales stick up more contestables going forward and Italy less? Will England perhaps reduce their long kicks and try to create some linebreaks from deeper? Will the penalty counts for both England and Ireland continue their form into this weekend’s match in Twickenham?
With only 3 rounds played it’ll be interesting to take a look back at this at the end of the 6 nations tournament and see what changes in the last 2 games. Sign up to our mailing list to be informed when that and our other analysis articles come out.