Callum McGregor announced his retirement from international football with Scotland before the serious stuff kicked off with Celtic in the 2024-25 campaign. This was sad for national team supporters with a Nations League and World Cup qualification campaign to come.

As of today, he has logged 508 matches and 39,817 minutes for Celtic. In addition, he’s appeared in 63 matches and 4,922 minutes for the national team. A lot of football has been played by the captain in the past decade or so.

In his favour, he started professional first-team football at age 20, like Kenny Dalglish. Meaning, unlike those pitched in from their late teens, he may see greater longevity into his 30s. That also depends on his natural body fitness, resilience, how he looks after himself and luck.

That last word is doing a lot of heavy lifting, and we have seen McGregor suffer injury in the last two seasons after appearing habitually in “most minutes by a footballer globally” lists. So, it seems a sensible call given his age (31) and desire to play for Celtic as long as possible. But, what about the performance dimensions?

I wrote about McGregor in these pages last October, examining whether he deserved the contract extension to the end of the 2028 season. My conclusion was “yes” despite obvious performance regression, on the basis that replacing McGregor like-for-like in the open market would probably be prohibitively expensive.

Let’s see how the performance metrics played out to the end of the season.

Defending

Firstly, defensive action quality:

Both defensive action success rate and the percentage of possession won back from defensive actions are down on the prior two seasons. Some of this could be attributed to subtle changes in team set-up. Under Brendan Rodgers, McGregor often had Matt O’Riley sitting with him when without the ball. O’Riley is a good interceptor with excellent defensive positioning skills. That may have diluted some of the work McGregor did but if we look at the volume of defensive activity:

We see that his defensive action volume increased over the Ange Postecoglou seasons. So, more defensive activity, but less successful in it.

That speaks to perhaps needing to protect the captain more as this isn’t a core skill for him. Specifically, Postecoglou’s “rest” defence usually incorporated the two fullbacks tucking in beside him. Perhaps O’Riley on his own is not sufficient cover for the skipper.

Ball Progression

Firstly, we’ll plot carries from StatsBomb with pack passes from myself:

Last season saw the lowest volume of ball carries since 2018-19. That is one metric where physicality and therefore age may be a factor. You might hope that would be compensated with more pack passes – that is, he’d carry the ball forward less often but instead play more forward passes.

But instead, forward passing volume is also the second lowest in the sample. For the first time in his career, the percentage of sideways passes in Celtic’s and the opponent's halves hit 80 per cent plus.

Another age regression indicator might be not seeing or reacting quickly enough to get the forward pass off. Equally, Rodgers’ Celtic were slightly less aggressive in their ball progression than Postecoglou. However, regression was evident between Postecoglou’s two seasons.

On a brighter note, the volume of deep completions – StatsBomb defines this as passes completed within 20 metres of the opponent's goal – increased.

Again, context. McGregor was part of Postecoglou’s sitting rest defence. Under Rodgers, there is tactical flexibility to allow him to get forward. The overall trend line shows this is another regressing metric. Finally, pure creativity is measured by the volume and quality of chances created.

Since McGregor settled into the anchor midfield role, his creativity has naturally fallen off. So, the recent seasons have seen low returns but all within a small margin of difference. Last season was on the lower end, however.

Pressing

Under Rodgers, the intensity and prevalence of pressing and counter-pressing have increased even compared to Postecoglou’s pressing-based game model.

We can see slight increases for McGregor but within a greater team emphasis. Again, as the eye can see, the trends are downwards for both presses executed and regains achieved. This would be another strong indicator of physical decline.

On Ball Value

StatsBomb’s OBV model has always liked McGregor which is encouraging for its efficacy. This metric has always had a positive score of up to 0.3, which is strong.

Last season’s 0.19 was not the lowest – that was 0.18 in 2021-22. However, as noted above, the trend is downward across multiple seasons. The OBV value includes passing, shooting, dribbling and carrying, and defensive actions.

Summary

McGregor’s 2023-24 completed season offered further clear evidence that natural age-based regression is happening. This is slightly blurred by the differing roles between Postecoglou and Rodgers. As such, the decision to retire from Scotland seems wise.

That’s six additional matches between now and mid-November that he will not be involved in. Add in the intensity of the pre-match training and the travel and there are significant benefits for him. That time can be spent on “active rest”. That is, more stretching e.g. yoga and Pilates-type exercises. Such activity can prolong a career by strengthening the body.

McGregor seems a very thoughtful and consummate professional. This decision to retire from international duty will not have been taken lightly. For Celtic and his aspirations as their on-field leader, it was an eminently sensible one.