David Turnbull, one-footedness and how Ange Postecoglou faces an interesting midfield dilemma - James Dailey

Just one week ago, I wrote my column lauding the performance track record of Celtic when Callum McGregor has played as a single pivot. We now have two more games to add to the sample, with the 3-0 and 3-2 defeats of Jablonec and Hearts. Despite comprising under four percent of Celtic game minutes since the start of the 2015-2016 season when Wyscout began covering Celtic games, McGregor’s games as a single pivot now constitute 5 of the top 18 games over the period for non-penalty xG differential.

While I believe McGregor played terrifically in the single-pivot role in both games, today I am going to focus upon one of his midfield partners, David Turnbull. I do so as part of an exercise to consider whether the mixture of McGregor as a single pivot and Turnbull as the left-sided central midfielder may be Celtic’s best midfield iteration for the current season.

The two radars above compare attacking and defensive radars for Turnbull’s 2018-2019 season at Motherwell with his 2020-2021 season at Celtic. After losing a season of development being out due to knee surgery and rehabilitation, he largely picked up where he left off at Motherwell. The volume of xG Assisted and xG went up as could be expected in a more possession dominant and attacking side like Celtic, but his defensive metrics held up well overall too.

READ MORE: Celtic tactical and data match report against Hearts as Greg Taylor continues his tactical evolution

However, 'midfield' is a pretty broad description, and his roles over the two seasons were quite different. At Motherwell, he played the vast majority of his minutes on the left side mostly in central midfield and actually did not score at all in a game when playing on the right. Here was his shot map from open play for league games that season, where we can see he scored just once from outside the penalty area from the right side:

Next, we have last season, in which he played the vast majority of his minutes as a number 10, or attacking midfielder, where we can see he again scored just once from the right side outside the penalty area. That was a goal versus Dundee United on December 30th, 2020, when he received the ball centrally and dribbled to his right to shoot.

Now let’s look at Turnbull’s Wyscout heatmaps from the two seasons, with Motherwell on the top and Celtic on the bottom:

So far this season, Turnbull started as either a number 10 or right-sided central midfielder and was recently transitioned to the left after McGregor was moved to the engine room base. Here are his heatmaps as a number 10 in the first Jablonec game, and then on the left in central midfield in the second. Turnbull obviously scored two goals in the second game, one of which was from a central position outside the penalty area.

I will now draw your attention back to the first radar and accompanying table I shared above, which has a metric titled 'Left to Right Footedness%'. David Turnbull was one of the most right-footed players in the league in both those seasons, and while a limited sample, that has continued so far this season.

What is the best position for David Turnbull?

I believe there is significant evidence that his best performance levels as a professional so far have come while he’s played as a left-sided central midfielder.

This makes some intuitive sense for such a one footed player, who is likely more comfortable cutting in onto his strong foot to shoot, while also affording better body shape to do so.

This leaves Celtic with an interesting dilemma. I have serious questions as to whether the introduction of James McCarthy as a single pivot will provide the sort of deep progressions, distribution, and “press busting” that Callum McGregor has in that role.

READ MORE: Celtic boss Ange Postecoglou reiterates recruitment message despite return of feel-good factor

With Hart and Starfelt already signed, and not ball playing iterations in their positions, can Celtic manage with just McCarthy as a single pivot versus more talented and athletic teams like Hibs and Rangers?

Even if they are able, is moving either McGregor or Turnbull to the right worth it? Will McGregor have to drop to a dual pivot and Turnbull return to a 10 role in order to help with buildup? As Turnbull’s shot maps suggest, is his shot selection and decision making good enough to warrant playing as a 10?

The next two weeks, with three games against higher-level, European-quality opposition, may offer important clues as to how Ange Postecoglou confronts these issues.

I think a lot of Celtic’s midfield questions could be answered if decides to retain McGregor as a single pivot with Turnbull on the left, and can find a talented, high-energy midfielder to play on the right. Someone who can cover box to box, tackle, press, and also has some goal scoring and creativity….you know, someone like Ryan Christie.