The international break is a prescient reminder that captain Callum McGregor has retired from the national team. Whilst Steve Clarke’s charges were impressively dispatching Croatia and Poland, he was spared the travel, match intensity and pressure for another two weeks.

I also remind you that early last season when McGregor signed a five-year contract, I did a piece on here. In summary: whilst his performance data indicated natural age-based regression, for Celtic to replace 30-year-old McGregor in the marketplace would be significantly more expensive than the decision to offer him an extended deal.

A year on, and benefitting from what will be ten weeks less travel and intensive international match exposure, what differences are we seeing in his performances?

Defending

As the holding midfielder in a three, McGregor’s defensive responsibilities are significant. Whilst never a strength in his game, it is nevertheless a necessity. We can consider both the volume and quality of defensive activity.

In line with the age-related decline, the volume of his defensive activity continues to trend downwards. This peaked at 9.3 actions per 90 in the 2018-19 season and is now 7.45. We do have to consider the context of team dominance, and the level of defending required. This season so far has seen the most difficult section of Champions League matches.

We can measure the quality of defensive outcomes through defensive action success rate and possessions won from defensive actions.

McGregor is winning a higher proportion of defensive actions this season than ever before – 58 per cent. 65 per cent of defensive actions result in Celtic having possession. This is up from 60 per cent last season. So, it seems that whilst he is not engaging in as many defensive actions, the quality of execution, and by proxy, decision-making, is improving.

This would fit a narrative of an older player who doesn’t need to engage the opponent more often due to sound positioning, and when they do, they are more successful.

Pressing

HudlStatsBomb has an excellent array of pressing and counter-pressing data. This sample for McGregor covers the SPFL only.

All the pressing metrics in terms of volume of activity and quality of outcome (number of regains) were trending down in an ‘isn’t he getting older’ style.

However, this season we are seeing a gentle uptick in pressing volume and outcomes. Pressing volume is not yet at 2021-22 levels. His overall pressing contribution took a dip under Postecoglou. We must, therefore, consider that the cause of this may have been personal orders and/or team instruction.

Pressing is more aggressive under Brendan Rodgers although that did not manifest in the McGregor numbers last season. So, attribution-wise, we could be seeing a dividend from the international retirement.

Ball progression

McGregor’s metier is setting the tempo of the game, and that means his ball progression abilities. Using a mixture of SPFL data for ball carries from HudlStatsBomb and pack passing for all competitions from my data.

The volume of both ball carries and pack passes is well up on last season's career low. Indeed, ball carry volume is the second highest recorded at 65.79 per 90 minutes. Pack passing volumes have not reached the levels demanded by Ange Postecoglou in his two seasons.

The number of carries may surprise given ageing, but in this season's Champions League, no player has covered more distance than McGregor at 50.5 km in the group stages. However, his top speed is 29.7 hm/hour. This is the 4th slowest top speed of the top 100 players by distance covered in the group stages.

What he is lacking in speed, he is making up for in the sheer volume of kilometres covered. This seems to be a pattern being repeated in domestic football, though we lack the velocity data.

The HudlStatsBomb data set includes a metric called deep progressions. This is the volume of passes or carries into the opponent's defensive third of the field. As such, it is a useful creative flag for central midfielders.

This seems a very nice proxy for age-based regression. From a peak at 27 years old in the 2020-21 season, there is a steady drop off of activity to the current season with 6.76 deep progressions per 90 minutes compared to a peak of 12.07. A drop of nearly 50 per cent. Increasingly, McGregor is not the vehicle by which the ball ends up in the final third.

Further up the field, we can look at creativity on the final third regarding the volume and quality of chances provided for others. This covers all competitions.

This is the least creative of McGregor’s seven seasons under review. He is down to less than one chance being created per 90 minutes and chance quality is down near 0.1 xG per chance.

Goal threat

Surely the dividend is in his increased goal threat given his five goals put him joint top scorer in the SPFL? Well, five from nine matches at 0.57 goals per game, and with 33 per cent shot conversion rate is the profile of a hot striker!

But, but but. My Huddle Breakdown colleague James did a nice job comparing McGregor’s hot start to the season with the basketball shooting prowess of Steph Curry. You can read it here. I have McGregor’s five goals from a total xG of 0.15. In total, his 19 shots have generated a xG of 1.06 (a measly 0.06 xG per shot). Long story very short – it is not sustainable.

Celtic seems to have a nice line in corner routines whereby Arne Engels, Nicolas Kuhn and McGregor work overloads, overlaps, underlaps and shots from a three-man routine. The goals are a lovely bonus but not indicative of a long-term trend.

His xG contribution per 90 minutes has stabilised over the last three seasons but remains around one-third of the 2019-20 peak.

On-ball value

Finally, here’s how HudlStatsBomb rates his overall contribution across all the on-ball activities.

This is another view where there is compelling evidence of gradual age decline. However, overall OBV has rallied to be the strongest it has been since the 2020-21 season.

Summary

Despite being the league's joint top scorer, the evidence of McGregor’s age-related decline remains real and clear. However, the decision to retire from international football seems wise and appears to have generated some dividends.

His sheer work rate and carrying of the ball around the pitch are increasing, and his decision-making in terms of defensive actions is improving. His overall on-ball actions are adding more value to the team than over the last three seasons. But there are trade-offs. He is getting the ball less often into the final third and his creativity is dwindling towards insignificant. Despite the goals, his threat to the opposition net is likewise continuing to slide.

There will be many attributions to this. Some will relate to a more mature, smarter player. Some will relate to Rodgers utilising his captain in a more manageable way. And some will relate to the freshness boost of missing the extra travel, training and match demands of international football.

All that said, what will remain true is the need for Celtic to be actively planning his succession such that he is not being relied on up every game.