We need to talk about Mooy...
Aaron Mooy assisted a goal and scored a penalty in Celtic's 2-0 victory over Dundee United, but there are still reservations about his ability to scale this up to Celtic's toughest challenges.
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Contents
Dundee United 0-2 Celtic
Rangers 2-0 St. Johnstone
Hibernian 6-0 Aberdeen
Ross County 3-0 Kilmarnock
St. Mirren 1-0 Motherwell
Livingston 0-0 Hearts
League Update
Dundee United 0-2 Celtic
Despite a moderate first half in terms of chance creation, a cluster of second half chances paired with a penalty ensured that Celtic earned a comfortable win. At the centre of this - and the centre of this newsletter’s discussion - is Aaron Mooy. Scoring the penalty and assisting the open play goal, the Australian is quickly cementing himself as a fan favourite. However, the midfielder’s play style - methodical and space dependent in possession and laissez-faire in defending transitions - provokes questions about his role in Celtic’s approach to overcoming bigger obstacles in the future.
Mooy’s current position in the team replaces Matt O’Riley. When O’Riley first joined Celtic, he had a tendency to drift wide in build up, receiving the ball outside traffic. This allowed Josip Juranovic to underlap into advanced central areas and this fluidity caused issues for opponents.
However, at the start of this season, this changed. O’Riley was encouraged to stay high and central, occupying this space more frequently himself. Ange Postecoglou has previously stated that he uses inverted fullbacks as a method for allowing attackers the ball in advanced positions more so this change fits with this philosophy; O’Riley was preferred to possess the ball in dangerous central areas. Free #8s are also key to Postecoglou’s Positionist system in how they can be used to generate positional superiorities; it’s more beneficial for a Celtic #8 to be disruptive by receiving the ball between the lines centrally than it is receiving wide with little pressure.
This change can be seen in the visual below.
Mooy’s in possession style is slow. His strongest attribute is often cited as his passing ability but this needs to be broken down more. His lack of speed (both physically and in terms of decision making) mean that he is more suited to dropping out wide to pick a longer pass with less defensive pressure than receiving between the lines in a dangerous position. This can be seen in the below visual.
As with O’Riley of last season, for this to be successful the space vacated needs to be occupied by another player. However, Celtic’s current right side does not allow this. Kyogo Furuhashi and Callum McGregor - the central supporting players - both have a natural tendency to veer left anyway, but Alastair Johnston and Liel Abada are very rigid in their positioning. Missing the underlapping Juranovic, Mooy’s movement now results in a wide cluster of players occupying the same spaces and passing lanes rather than a slick disruptive rotation. This is ineffective in possession, but also harms Celtic’s pitch coverage for when the ball is lost. This, in turn, damages their ability to counterpress which results in long chases back to stop counter which Mooy is also not suited to. The below visuals highlight the rigidity of this right hand side.
This analysis is not a comment on Mooy’s ability, but rather suitability. The debate of generalists v specialists is one that has been at the forefront of Celtic tactical discussion since Postecoglou’s arrival: how important is it to be able to do more than a role traditionally demands? It’s the same line of thinking that prompted this newsletter’s previous article on Postecoglou’s use of centre backs in this system, and discussion surrounding whether Giorgos Giakoumakis’ instinctive positioning in the box could make up for his negative impact on Celtic’s build up tempo and rhythm.
Mooy’s strengths could fit into the team if the rest of the right hand side could compensate in the same way that Juranovic did by occupying the space that O’Riley initially vacated. However, the current personnel create an environment in which pursuing Mooy’s strengths highlights rather than masks his deficiencies. This is fine against Dundee United, who were unable to capitalise on Celtic’s lax defensive transitions on that side, and ultimately were unable to defend the box well for the entire duration of the match, but is less likely to be fine against better opposition.
Michael Beale’s Rangers emphasise central control and transition attack within their play style (by remaining very compact in the centre). The trends highlighted in this newsletter suit this from a Rangers perspective; it could become very easy for Celtic to be shown wide and resort to aimless aerial crosses if this system’s central weaknesses clash with Rangers’ central strengths. Perhaps these deficiencies aren’t endemic in games where time and space are allowed, but falling down on some of the core principles of Celtic’s Positional Play - creating positional superiorities, passing lanes maintained by positional rules, and well-spaced pitch coverage - could be very damaging against a team that are able to exploit these weaknesses.
Stepping up to ‘harder’ games is not simply about difficulty, but rather the dynamic of the game. Better teams don’t just have better players, but are more able to problem solve and exploit weaknesses. Whether Mooy should start Celtic’s ‘tougher’ games is not exclusively about whether he can perform the same actions at a higher level, but whether those actions are desirable or effective against those teams. Celtic’s fluidity has helped to overcome Rangers repeatedly in Postecoglou’s era, and damaging this with the selection of Mooy within this specific right hand side may not be the best approach for Celtic’s success in these matches, even if some of his strengths have led to chances against weaker teams in the league.
Rangers 2-0 St. Johnstone
A dominant performance - buoyed even more by a penalty from a St. Johnstone handball and a straight red card for Nicky Clark - led to a comfortable win for Rangers. Michael Beale’s system is becoming more recognisable by the game, and has now received the boost of Todd Cantwell’s signing and Ianis Hagi’s return from injury.
Cantwell’s debut was the most interesting talking point of this match. Adopting a much less focused role than Ryan Kent, Cantwell drifted about the pitch with the primary intention of linking up play. This free role was previously afforded to Kent under Giovanni van Bronckhorst but - in that system - resulted in a massive burden on the English winger, with the task of ball progression falling solely at his feet.
Rangers’ system uses a double pivot to sit atop two centre backs to create a 2-2 rest defence structure. This gives freedom to the fullbacks, who provide the team’s width almost exclusively. This is highlighted in the below visual.
The wingers are then free to come inside. As mentioned, Cantwell can be then used to link up play with lessened positional responsibility while Kent’s role has been redefined. Instead of being allowed to pick up the ball anywhere and then being tasked with progressing it with carries, he is now part of more structured link up with near sided midfielders and Borna Barisic. By receiving the ball in a more consistent area (deep and central, highlighted in the below visuals showing his received passes and the differences between Barisic and Tavernier in possession), the decision is put onto defenders: press him as he receives (leaving space behind) or allow him to receive freely and turn. This takes the onus of decision making from Kent, and simplifies his duties. By receiving deep, he can still make the driving progressive runs that Van Bronckhorst sought to exploit but without the burden of dictating the whole process himself from decision to execution.
Beale’s central compactness is the key defining hallmark of his system. It’s the principle that Van Bronckhorst changed when taking over from Steven Gerrard (and Beale as assistant), and is now once again the preferred approach of the Ibrox side. Van Bronckhorst’s Rangers were criticised for countless crosses into the box with a low success rate. The below visual from this match highlights how emphatically Beale has resolved this with his approach, with the majority of chances coming from central areas as a result of progressive passes.
While the meta discussion around ideal approach could yield different results, it is without doubt that Beale’s system is more suitable for this group of players. By having the ball carrying and space manipulating specialists (mostly Rangers’ wingers) in from the wing and the excellent crossers (fullbacks) wide, the strengths of the squad are well exploited. Additionally, the central midfield choices under Van Bronckhorst were often criticised, with players like John Lundstram being tasked with final third runs. By using the double pivot to sit atop the rest defence structure, these players now have an emphasis on defensive transitions, possession maintenance, and deep progressions rather than advanced runs and attacking creativity. This also reduces the defensive burden on the ageing James Tavernier who - on the far side of peak age for a fullback - is becoming less able to recover from the high positions he takes up in possession.
Hibernian 6-0 Aberdeen
Ross County 3-0 Kilmarnock
St. Mirren 1-0 Motherwell
Livingston 0-0 Hearts
xPoints Table
Over the last month or so, outliers have generally started to fall back in line with their xPoints. Even Hearts this week dropped points while picking up 2.46 xPoints, pulling them slightly back from their previous overperformance. While this as an individual result pushes the overperforming Livingston back out slightly, the tight cluster of most teams around the central line in the above visual shows how - as a longer trend - very few teams are earning results overly different to what is expected of them based on their performances.
The biggest current outlier is Celtic. Last season, a previous iteration of this model correctly assessed that Celtic were underperforming and were actually playing better than Rangers despite being six points behind at the time. While this is not intended to be an entirely predictive tool (especially not for the strict confines of a 38 game season), identifying differences of that nature in a tight title race is useful for forming predictions. However, the difference this season is that, even exclusively looking at xPoints and not actual results, Celtic are still ahead; their overperformance is simply making the gap appear larger than it actually is versus the predicted switch in the league leaders last season.
This newsletter often assigns deviation from xPoints the tag of ‘luck’. The model used is assessed over thousands of games across tens of leagues worldwide and, generally, teams fall in line with their xPoints. By identifying that underperformance or overperformance is generally unsustainable, predictions can be made regarding regression and, in most cases in football, variance is exactly that; football is a low scoring sport and luck plays a big role.
However, as with all models, it is imperfect. Outliers exist. The frequency of outliers that do not regress is tiny, but still present. It is entirely possible that Celtic have found a blindspot in the xG model used, or are affected (positively) by an extraneous variable that this approach cannot yet account for. At this point, outliers of this nature are so infrequent that conclusive statements cannot be made about what might cause it other than extended ‘luck’. The key, however, is that if Celtic are such an outlier, they would be the exception rather than the rule. The idea that Celtic are unlikely to keep up such a streak (its interruption simply being a couple of games with dropped points rather than a total implosion) is a fairly inoffensive hypothesis, but the model still indicates that - regardless of their overperformance falling in line or defying the odds - Celtic are still currently the best performing team in Scotland.