In a regular column, Matt Rhein looks at the numbers beyond the results in the SPFL Premiership and, most of all, for Celtic. In this edition he looks at how Scott Brown is leading the way in a stat category there have been no previous public record of in the SPFL; expected secondary assists.
One of the most iconic images is Celtic history is Billy McNeill accepting the European Cup to cap off the best day in Celtic’s history. McNeill’s strong leadership was the spine of the legendary XI that will live in the memory of Celtic supporters forever. Peter Swales said of McNeill:
“If ever a man was made for a specific club, it was Billy McNeill and Glasgow Celtic. His heart was always at Parkhead.”
While not quite the same historical significance, another Celtic captain is helping to lead the Hoops to a possibly historical season. Scott Brown has been vital towards Celtic being undefeated domestically and on the cusp of winning a treble this season. The most incredible part is the fiery Celtic captain looks to be a new signing in comparison to the player we saw last season. Brown seemed to be winding down his career when Ronny Deila left Celtic. Now Scott Brown is the proverbial first name on Brendan Rodgers’ team sheet.
Often times it is thought that players like Scott Brown’s contribution are hard to quantify statistically. Not true, I say! During the Champions League this season, there would often be tweets sharing Brown’s pass completion percentage from that match as proof of his great performance. Scott Brown has been incredible this year numerous times. High pass completion percentages from individual matches are not something to prove this. For example, in the 2-0 defeat to Borussia Monchengladbach, where Celtic looked poor, Scott Brown had a 96% pass completion rate. In Celtic’s two draws against Manchester City in which Celtic objectively played much better than in that loss to Gladbach, Brown had a lower pass completion rate at 95% and 91% respectively. Sometimes completing passes does not tell you much.
The issue with pass completion percentages is that it treats every pass the same, when some passes are more important in football than others. I have discussed the idea of expected assists before, though a player like Brown who wins possession and makes the key first pass to start a Celtic attack might not see their contributions reflected in xA. Statsbomb Services’ Ted Knutson and Thom Lawrence wrote about xGChain which was an attempt to quantify players like Brown’s contribution to an attack. Statsbomb takes all the possessions a player is involved in, take the shots from those possessions, and then sum all the expected goal totals from those possessions.
Unfortunately, I do not have access to that type of data. However, the good folks at StrataBet do now provide myself and the Norwegian who is at least top 10 in most-well-known-Norwegians-by-Celtic supporters with similar information. Specifically, they can tell us who passed the ball to the player who made the pass that lead to an attempt. Referred to as a secondary assist or sometimes as a pre-assist or ‘hockey assist’ (the version with ice) we can apply the same idea as xA or xGChain to see which players are most involved in the build up for their team’s attack.
When we look at the players who have the highest expected secondary assists (or xSA) in the SPFL, Scott Brown is leading the league. Brown has a higher xSA total than Aberdeen (and Player of the Year shortlist candidate. I know) Jonny Hayes, as well as teammates Scott Sinclair and Patrick Roberts. Brown’s ability to successfully start Celtic attacks is shown in these stats and shows how important he has been to the Hoops success this season.
While he is no longer the attacking midfielder he was when he first came to Celtic from Hibs, Brown has improved going forward on the attack this year. He only has 1 league goal, but his expected goals is 2.72 this season, compared to only 1.33 last season. There is not xA numbers available for last season, but Brown also has a respectable 2.49 xA despite usually being the one starting Celtic’s attacking moves, rather than being there towards the end. These totals together put him at a xG+xA of 5.21, which is 10th at Celtic.
There may never be a captain for Celtic to achieve what Billy McNeill did for Celtic, however Scott Brown has the opportunity to put himself among the legends of the club. Two (at the time of writing) league matches away from an undefeated season and a final at Hampden are all that separate Brown from reaching nearly unparalleled territory, quite the feat at a club as historic as Celtic. If Brown can continue to contribute to the team’s chance creations as he has so far this season, Celtic must feel pretty good about their chances of making history.
This article was written with the aid of StrataData, which is property of Stratagem Technologies. StrataData powers the StrataBet Sports Trading Platform, in addition to StrataBet Premium Recommendations.