In the aftermath of yesterday’s 3-0 loss to Zenit St. Petersburg, the internet has had plenty of thoughts about who the blame for Celtic’s form this season. These thoughts range from lukewarm to spicy hot, such as seeing on one Celtic message board say that “Brendan Rodgers is a fraud”. Regardless, Celtic supporters have had numerous ideas on who to blame for the result in Russia last night.
One of those facing the brunt of the blame for both last night and Celtic’s form dipping this year compared to last is Mikael Lustig. The 31 year old Swedish fullback is in his seventh year at Celtic and has become a cult hero for much of the Celtic fan base. However, it seems the Swede has seem his form dip this year. Before this season, the right back was one of the more consistent players for the Bhoys, but from observation it seems Lustig has not played as well as he has most of his Celtic career.
The above map was created by Dougie Wright and shows where the chances created against Celtic have come from in league play. The darker the green is on the heat map, the more chances have come from that area. It becomes pretty clear that teams in the SPFL see Lustig as a weakness in the Celtic back-line and are trying to expose the area he patrols.
And if we look at the numbers for both the Celtic defense and the rest of the league, we see that to be the case. In the above table, we have the number of Key Passes (or the pass that set up a shot) teams concede on the right wing, the percentage of total key passes a team concedes that comes from the right wing, that percentage of key passes from the right wing compared to the league average, the expected goals from key passes conceded on the right wing, the percentage of a team’s xG conceded that came from key passes on the right wing, and how that percentage compares to league average.
As we see, the numbers are not kind to Mikael Lustig this season. Though Celtic have conceded about the average number of key passes from the right wing, they have conceded easily the highest percentage of the key passes coming from the right wing. 28.57% of the shots Celtic have allowed originated from a pass on the wing Lustig usually patrols, which is 12.21% higher than league average.
Celtic have also conceded by far the highest xG in the SPFL from key passes from the right wing at 5.07, which is 37.62% of their total. This is 22.03% higher than the average in the SPFL. The next highest percentage of xG conceded from Key Passes on the right is 17% less than what Celtic have conceded. Teams have clearly pinpointed Mikael Lustig and the right side of Celtic’s back line as the area to attack and these numbers show that they have clearly been able to do that.
Celtic’s recruitment strategy has been one of the more common places most have put blame for the result in St. Petersburg. Some have asked why a replacement for Lustig was not found either in the summer or January transfer market. Brendan Rodgers has been reluctant to play Christian Gamboa this season, meaning Mikael Lustig has played a lot of football this season. Both by observation and numbers have suggested that Lustig has struggled this season. Perhaps the high number of minutes he has played both for Celtic and Sweden has caused this dip of form, but if this continues Celtic will have no choice but to look for a replacement for the long serving Mikael Lustig.
It seems to be the standard now for Rangers to find themselves in the headlines of Scottish football, both for matters on and off the pitch, on a seemingly weekly basis. From memory, we have had Pedro Caixinha sacking, Carlos Pena being sent back to Mexico and his choice of handkerchief, and Josh Windass’ various hand gestures to fans as examples of off field shenanigans surrounding Rangers this season. However, among the headline grabbing antics at Ibrox, Daniel Candeias has quietly put together one of the better campaigns in the SPFL this season.
I discussed the idea of expected assists last season, but thought this would be a good time to have a refresher on this metric. Expected assists applies the idea of expected goals to those creating the chances. Using the same model we use for xG, xA applies that same number to the player who created the chance via pass. So if Daniel Candeias passes to Alfredo Morelos and Morelos takes a shot worth 0.2 xG off of it, Candeias gets an xA of 0.2. This is an attempt to quantify the type of chances a player creates, rather than something like passes completed percentage.
If we look at the expected assist leaders for the SPFL Premiership this season, we see Candeias is by far and away the league leader. Through February 11th, Daniel Candeias has a total xA of 9.06. The next highest player in the SPFL is at 6.08, quite a ways away. He has an xA per 90 minutes of 0.41, the highest of any player who has played at least 700 minutes this season. He has the highest expected assist numbers from free-kicks, open play, and is 4th in xA in set-pieces. Last season, Niall McGinn had the highest xA in the league and he had an xA per 90 of 0.35, so Candeias is averaging a higher expected assists for every 90 minutes than league leader McGinn did last year. All of this is to say Candeias has been one of the best creators on attack in the SPFL Premiership this season.
Looking at Candeias’ pass map from open play this season above, it is no surprise to see most of his contributions have come from that right wing. From that wing, Candeias has found James Tavernier for 10 key passes, Alfredo Morelos 9 key passes, and Josh Windass for 9 key passes. Most would agree those three are Rangers most dangerous attacking threats, so the Portuguese winger finding them so often has certainly helped lead to his success this year. Furthermore, looking at where the average location for those players were when Candieas set them up for a shot, we see all of three of them located in the “Danger Zone”. This is the area in the 18 yard box in between the 6 yard box and these shots have been found to be the most likely to be scored. When Daniel Candieas is setting up the likes of Morelos and Windass, he is finding them in the most dangerous locations on the pitch where they can score goals.
Against Aberdeen at Pittodrie on December 3, Daniel Candeias sets up the winning goal. He times his run well on the right and puts a first touch low cross perfectly onto the foot of Josh Windass, who is square in the “danger zone” of the box and able to finish, leading to a man hug for Candeias from Graeme Murty. Run on the right, cross into a dangerous position where his teammate is waiting and can easily finish a high xG chance for a goal.
Despite the score finishing 0-0, Candeias had a very good match against Celtic in December. We see another example of what he has done so well in that game. His cross finds an open James Tavernier in the heart of the danger zone, where Tavernier’s shot is only kept out by a good save by Craig Gordon. Another cross on the right to a teammate in the danger zone, who forces a good save from the keeper from a high xG chance.
This season, most of the more ardent Twitter debates in Scottish football have been discussing if certain Rangers players are actually good. Never-ending feuds about whether the likes of Josh Windass and Carlos Pena are good players or not are found at various corners of the great time waster known as Twitter. Daniel Candeias thankfully does not draw such hard line opinions. Most seem to know he is valuable to Rangers success this season. However, it is a bit surprising his praises have not been sung at such a level as they have with someone like Alfredo Morelos by Rangers supporters. Both have been key cogs to Rangers attack this season and Rangers will need them to continue their form if they are looking to finish second.
One avenue to try and create understanding about analytics in football is to use them to praise players. Letting a player know he has good stats, what those stats mean on a basic level, and what he is doing to get those impressive metrics can help foster acceptance and further understanding from players. Which brings us back to our pal Kris.
If I told Kris Boyd, “Hey your expected goal numbers of 7.90 are great,” he would most likely look at me as if I had four heads, with two of the heads telling him to switch to a vegetarian diet. However, he might be more receptive to the idea if I said something along the lines of “we have this stat that says you have done a great job at creating shots that are more likely to be scored. If you continue to be able to get shots centrally in the box, you will likely keep scoring goals,” he may be more receptive to the idea. A player may be more interested in analytics if it is includes praise and includes an easy to understand idea to lead to continued success.
This hypothetical discussion with Kris Boyd does indeed contain some of the reasons why he has seen a resurgence on the pitch this season. Boyd has 9 non-penalty goals and 0.56 non-penalty goals per 90 minutes so far this season, only Alfredo Morelos has more in the SPFL Premiership. He also has had good underlying statistics this season, with an xG of 7.90 which is 4th in the league and an xG per 90 of 0.54. These xG stats show his goal scoring has been sustainable for Kilmarnock this season.
If we compare these stats to the same numbers from last season, we see a clear improvement. Last season, Kris Boyd scored 7 non-penalty goals and 0.32 non-penalty goals per 90 minutes. Like this year, Boyd’s goals were about what you would expect based on his expected goals numbers, with an xG total of 7.38 and a per 90 average of 0.30. We see the striker/pundit has already surpassed both his goals and expected goals total from last season and we are only into February. While you may or may not enjoy his TV work this season, Boyd’s goals have been a big part of Kilmarnock’s success this season.
Not only has the Killie striker been knocking in the goals this season, but he has been a bigger part of the Ayrshire side’s attack overall. Looking at his expected assist numbers from last year and this year, we see last season Boyd had 3 assists, an xA of 1.67 and 0.08 xA per 90 minutes. This year while he only has 2 assists, Boyd already has an xA total of 2.58 and a per 90 of 0.16. His contributions to the Kilmarnock attack has improved, with improved shooting and creation statistics this year.
Given that Kris Boyd is 34 years old, this improvement from last year is a bit surprising. Strikers typically regress at that age, something many may have assumed was happening last season with Boyd. So the question therefore becomes what has happened between last year and this year to see this improvement from the Killie striker.
During this campaign, Kris Boyd has been able to get far better shots than he did last season. He is averaging 0.16 xG per shot this year, while he only averaged 0.11 xG per
shot in the 2016-2017 campaign. To simplify this, on average every shot Boyd takes this year has had a 5% higher chance of going in based on where and how he has been shooting. Not only is he taking higher quality shots this season, but he also taking more of them, averaging 3.4 shots per 90 minutes this season and 2.59 per 90 last season. Taking more and better quality shots is clearly one of the reasons for the rise in Boyd’s form this season.
Thirty-four year olds do not usually see those types of jumps in those numbers from one season to the next, so why has Boyd? Well, he has some help shouldering the load at Kilmarnock this season. Last season, Boyd was the only Killie player who played at least a third of the available minutes in the league last season (1140) with an xG per 90 of at least 0.3. Only Souleymane Coulibaly had an xG per 90 of over 0.2 at Kilmarnock last year, and he left midseason. No player who appeared in at least 1140 minutes averaged at least 0.1 xA per 90 or more for Killie last season. Boyd was the focus of the Killie attack last season.
The current campaign must feel like a weight has been taken off of Boyd’s shoulders. Though both playing less minutes than Boyd, Eamonn Brophy and Lee Erwin are both averaging over 0.2 xG per 90, at 0.68 and 0.23 respectively. Both are options off the bench for Kilmarnock that are capable of scoring. Along with other scoring options besides Boyd, the Killie attack also has considerably more options for players that can set up Kris Boyd and his fellow strikers.
As previously mentioned, no Killie players averaged over 0.1 xA per 90 minutes last season. Boyd has already bested that himself, averaging 0.16 xA per 90 minutes, but he is not alone. Along with Boyd, Gary Dicker, Brophy, Jordan Jones, Adam Frizzell, Stephen O’Donnell, Erwin, and Rory McKenzie have all appeared in at least a third of Killie’s available minutes and have averaged at least 0.1 or higher xA per 90 this season (0.20, 0.19, 0.17, 0.16 , 0.14, 0.13, and 0.12 respectively). Boyd is clearly flourishing with more creative support around him.
While he may not be interested in knowing the math behind it, there is no doubt Kris Boyd has been one of the better strikers in the SPFL according to the stats. Analytics skeptical players like we can presume Boyd is may not be interested in regression models and scatter plots, but they are surely interested in becoming better players and they are definitely interested in receiving praise. Praise and recognition for a player can lead to more playing time, improved contracts, and a move to a bigger club. Framing the discussion around football analytics to a skeptical player about how it can improve their career may be a bridge to understanding for them.