It feels like I have been writing about the decline of Brown for some time now. But here we are with the captain playing the equivalent of 35.22 matches this season. The dependency on him seems no less onerous. How is he continuing to rage against the dying of the light?
Defensive Performance
What I will make clear up front is that further to my end of season report Brown: Growing Old Gracefully, the trend is for a gradual decline in overall involvement. His performance levels improved markedly after the winter break last season. He performs a unique role in the team, sitting in front of the defence, not expected to contribute much to attack (but 4 goals this season!).
His role this season has shifted subtly. Rather than be more integral to the midfield, he is more likely to sit back into the defensive line. With both full backs attacking this season, there is a need for extra midfield cover. Previously whilst Tierney remained high and wide Lustig would tuck in. Now that Lennon seeks equal pace on the right side, so Brown covers more and builds less.
In terms of core defensive actions:

The trend continues of less successful challenges and interceptions. Unsuccessful ones are creeping up meaning the Defensive Action Success Rate % is reducing.

For context, 62% is 11% higher than the next highest midfielder, McGregor.
The one aspect of this that is degrading the most is aerial challenges. Whilst Brown is losing less tackles, he is losing more headers.
Another indicator of decreasing mobility is that Brown is Packed (bypassed by forward passes) 12.18 times per 90m compared to 9.72 last season. Celtic are generally slightly more open than under Rodgers, the corollary to more aggressive vertical football (Celtic defenders Packed per 90 has gone up from 9.92 to 11.61 per 90m).
So, decline for sure but it continues to be very gradual.
Ball Progression
Celtic are generally less patient in their passing. Average completed Open Play passes is down from 531 per 90m to 442. Brown’s passing numbers are therefore declining as well.

I’d say this is more to do with team style than any individual reflection on Brown.

Indeed, this smiley face reflects Brown is completing 8.32 Pack Passes (forward passes that take out opponents) per 90m compared to only 5.22 last season. He is setting the example on the pitch for the manager, as you’d expect.

Further good news is that xA is back up to 17/18 levels whilst there has been a spurt in xG, albeit all from a small base. Brown is not matching his Goal rate of 0.11 per 90m by his xG but that prolific run of 4 goals in 7 games may not be repeated! I can inly emphasise these numbers are from a low base, and may be reflective of Celtic’s more attacking outlook under Lennon.
His involvement in Secondary Assists (the pass before the assisting pass) is down very slightly, and again can be explained by him sitting deeper in general.
If we look at complete involvement in forward actions, his Total Impect per 90m is 49.03 which after a dip last season is back above 17/18 levels (47).
Conclusion
In line with Celtic’s more direct approach, Browns slightly more defensive responsibilities, his involvements overall are decreasing. From 85 possession events in 17/18 he is now involved in 70 per 90m. His performance mirrors changes to team style more than anything.
Brown continues to evidence “managed decline”. No falling off the performance cliff here (see Rogic).
The hints at decline are still there – DASR% down, Packed more often, decreasing aerial prowess. But the message is the same as last season. He is still performing a role no other squad member does. He needs help and with Bitton back to fitness I have no idea why the captain has not been rested on occasion. Brown’s numbers are not going to go up, especially defensively which is his core responsibility.
There doesn’t appear to be activity in the January window around defensive midfield experienced cover so maybe Bitton will be utilised for the run in.
The captain continues to need help.