Is Moritz Jenz a better option for Celtic than Carl Starfelt?- James Dailey

It may be hard to believe, but Moritz Jenz has already played over 1,600 minutes across three competitions in a Celtic strip. That offers a decent sample size to check in on how he has performed while filling in for the injured Carl Starfelt.

Concerns were expressed in this column from July of this year about the German's performance data profile relative to the very specific demands placed upon centre-backs in Ange Postecoglou’s playing style. 

Were those concerns justified? First off, there will be a comparison drawn between the Hoops loanee in league games so far this season and Starfelt's performances in the Scottish Premiership last year.

The first radar compares the two by breaking out the four main components of StatsBomb’s on-ball value (OBV) metric. The second breaks out various defending-centric metrics to try to ascertain any potential differences. We can see from the first radar that the German has been very productive in progressing the ball while running, as well as offering some value via his shooting. 

However, the volume of shots for a centre-back is low overall, and he has taken only six so far in his limited minutes in league games. 

We should not ‘penalise’ him for that but should also not necessarily count on that being a durable skill either. Excluding the shot component of OBV, the two players have been comparable. 

Their pass OBV was similar, with Jenz’s more adventurous passing creating some value but also offset somewhat by his higher turnover rate.   

The glaring difference in the Swedish international's favour is the disparity in defensive action OBV. That imbalance is the reason for including the second radar, which offers a more granular context. 

The Parkhead loanee's recent penalty-conceding foul appears to have had a disproportionate impact, given the nine-plus game sample size. In addition, it can also be seen that he has been less advanced on (per average defensive action distance) and also less efficient in regaining the ball.

Perhaps most surprising is that he has not been as effective aerially as his prior profile suggested. That may be part of acclimatising to a more physical league and/or simply typical variance from a relatively small sample size. 

The main analytical conclusion from the July column was that some of the German's apparent weaknesses might make his ability to perform well in the Champions League a challenge. 

Of the 72 centre-backs that played at least 300 minutes in the six group-stage games, Jenz ranked 59th in overall OBV. 

Here is the defender compared to the left-sided centre-backs for the two teams that finished immediately ahead of the Scottish champions in the group:

Both players provided significantly higher OBV to their teams, even excluding shots, which also reasonably aligned with their relative styles of play. 

For example, Mykola Matvienko’s 0.16 in defensive action OBV was within the context of Shakhtar Donetsk playing a deeper defensive line and counter-attacking strategy. Josko Gvardiol, meanwhile, offered a more balanced distribution of OBV playing for an RB Leipzig team in a transition between managers. 

To his credit, Jenz was reasonably effective on the ball with respectable levels of pass and dribble and carry OBV but, once again, his defending-related metrics were less than ideal. 

As with many Celtic players, however, it was the 23-year-old's first Champions League experience, and he remains at a relatively young age. 

That said, given the body of evidence over his time prior to arriving at the Hoops and his inability to be more dominant domestically so far, it appears likely that the club remains in need of at least one upgrade at the centre-back position ahead of a potential 2023 campaign in Europe's premier competition.