Injuries have unfortunately become a hot topic amongst the Celtic support following Kyogo Furuhashi’s unfortunate hamstring issue last Thursday against Real Betis. The circumstances of the injury were understandably controversial, as the game was a ‘dead rubber’ and the loss of Kyogo for any period could be very costly given the crowded fixture list between the game and winter break. I started commenting on Twitter in July on the topic relative to Ange Postecoglou’s physically demanding style of play and Celtic’s fixture calendar, but had not done much examination of history up until now.

This August 24th column examined some potential risks surrounding Ange’s playing style should the team end up conceding higher chances to opponents even if overall performance levels were strong. Domestically, this risk was subsequently reduced as Celtic have been limiting opponents to very low level of chances overall. In fact, Celtic’s season-long average of non-penalty xG conceded in the league is currently below that conceded in the 2018-2019 season. Since the transfer window closed, the average in league games since has dropped to below the 2019-2020 average, which was the lowest since xG data became available.

Unfortunately, there are many forms of risk, and injuries have become quite a problem so far this season. Ironically, some of the shift in playing style which has resulted in suppressing opponents’ chance creation, while also probably reducing our own, has likely been due to injuries. Both Callum McGregor and Kyogo were unavailable for a period post-September international break, and Tom Rogic was recently absent for a number of weeks. I will not list all of the players who have missed games due to injuries, but it has been extensive.

READ MORE: Ange Postecoglou full transcript: Kyogo's cup final chances assessed

This drove me to take a look at Ange’s career dating back to his time in charge at Brisbane Roar starting in the 2009-2010 season, and attempt to try and ascertain what may be occurring. I first wrote on Twitter in July about the potential risks of Ange’s intense and physically challenging playing style when applied to Celtic’s extremely demanding calendar. That was mostly intuitive speculation, but today let us examine some historical perspective.

This graphic shows the club games played by teams Ange has managed since his first season in Brisbane.

Celtic Way:

This shows how Ange’s teams in Australia played significantly fewer games than either Yokohama F. Marinos or Celtic. Celtic currently have 52 games scheduled for this season, with the potential for additional Europa Conference League and Scottish Cup games, with deeper runs in both possibly taking the game total closer to 60.

But it is not just the volume of games that concerns me.

Next, we look at the number of games played with four games or less in between fixtures:

Celtic Way:

I’ve added two columns here, showing the number of games with four days or less in between fixtures, but also what percentage those games were relative to the overall games played. This perspective offers additional information as to the physical demands on players, but also introduces another consideration - performance.

In Ange’s first season at Marinos, his team played the most games he had ever managed, with 58% of the games on four days or less of recovery. They finished 12th that season in the table, but also underperformed their expected points (Wyscout’s xPts model), with 41 points versus 49.5 xPts. The game volume and fixture congestion lightened up in the 2019 season, in which Marinos won the title with 70 points versus xPts of 57.4 – a significant overperformance. Ange’s last season at Marinos saw a much more congested fixture list, as the team qualified to play in the AFC Champions League. Unfortunately, the team finished 9th in the table on 47 points versus 58.2 xPts – again a significant underperformance.

This perspective led me to ask the following questions: Who else has had this potential problem? Who also plays an extremely physically demanding playing style that played/plays a lot of games?

How about Marcelo Bielsa?

Celtic Way:

Bielsa’s had a period of success at Leeds, with an act of sportsmanship preventing promotion out of the English Championship in 2018-2019, followed by promotion and then a successful initial English Premier League campaign in 2020-2021. However, we can also see that while the number of games played was relatively high in the Championship seasons, the rate of fixture congestion was significantly less severe. Also, his team had been heavily impacted by injuries prior to the 2018-2019 playoff tie versus Derby, and the following promotion campaign was broken up by a long break due to the pandemic.

Whether fairly or not, Bielsa has even been received some criticisms related to “burnout,” and he’s been defensive this season about the potential role Leeds’ relative squad size has had on their poor start to the current campaign. As we can see from the graphic, Ange Postecoglou’s players could laugh at the minutes being played by Leeds players.

READ MORE: Celtic's sustained silence on Bernard Higgins issue is more damaging than quiet in the stands

I do not have access to readily available information on injuries across leagues and clubs, nor the ability to segment managers’ playing styles by physical demands.

It would be ideal to have that sort of information to conduct a larger-scale analysis of the potential impact of fixture congestions relative to demanding styles of play. However, sometimes analysis is about trying to assess risks and potential rewards with imperfect or incomplete information.

This exercise, combined with the injury record for Celtic players so far this season, has me more concerned about the associated risks than prior to conducting it. With a manager who has never navigated a season with these threats, and a club culture that resulted in it taking over four months to hire a new head of sports science, I worry this issue may be persistent at least through the remainder of the season.

Some badly needed reinforcements appear to be on the way in the upcoming transfer window, but the calendar will remain unrelenting.

Let’s all hope the additions combined with the recent partnership with The Tumeric Co is sufficient.