Don't sleep on Aaron Mooy's growing Celtic influence

The Australian international's first league start, away at St Mirren in September, coincided with the Hoops' only dropped domestic points so far this season as they fell to a disappointing 2-0 defeat in Paisley.

Hooked at half-time by Ange Postecoglou that day, Mooy’s underwhelming display at his former club led many to question the signing of the former Huddersfield Town and Brighton midfielder.

Due to Callum McGregor’s injury, however, the 32-year-old has found himself back in the team in recent weeks. He quietly impressed in three consecutive league starts against Hibernian, Hearts and Livingston before dropping to the bench against Dundee United at the weekend.

When it was confirmed that McGregor would miss a significant number of games following an injury picked up in the Champions League match away to RB Leipzig, many would have expected Mooy to be one to step into the Celtic captain’s role at the base of midfield.

However, Postecoglou has chosen to utilise Matt O’Riley in that role with Mooy deployed further forward in one of the two more advanced central midfield positions.

Alongside O’Riley and Reo Hatate, Mooy has now started to show some of the qualities that convinced the Celtic manager to bring a player he knew well from his time in charge of the Socceroos back to Scottish football.

He contributed three assists in those three league starts in a row recently with the Celtic assistant manager, and fellow Aussie, Harry Kewell highlighting Mooy’s professional reaction to that early setback against St Mirren as key to his upturn in from.

"It was part of the structure that the manager wants to play but obviously (Mooy) felt hard-done-by so he went out there and he wanted to work even harder," Kewell said.

"That just goes to show the professionalism that he’s got. Aaron has gone from there and he’s just getting stronger and fitter.”

The former Shanghai Port man’s growing influence can also be seen in his early season data.

The above chart uses Wyscout per-90-minute data converted into percentile ranks to compare him with other central midfielders (minimum 400 minutes played) in the Scottish Premiership.

There are two important caveats here that should be mentioned. The first is that this is still very much a small sample size; Mooy has only clocked up 506 league minutes so far this season.

Secondly, we would always expect Celtic players, given the nature of their dominance domestically, to score well across most of the metrics, particularly the attacking and possession ones.

That said, these initial numbers still show Mooy impressing in a few key areas.

He scores well in terms of his goal contributions, thanks to those three assists. His combined expected goal contributions are steady with 0.19 expected goals (xG) per 90, he has certainly passed up a good few chances to open his Celtic account, notably at Tynecastle, while his 0.24 expected assists (xA) per 90 is the third highest in this dataset.

His possession numbers are impressive too. As mentioned, we would expect to see Celtic midfielders dominate this section but Mooy boasts the highest number of progressive passes (10.67 per 90) in this early-season dataset.

He also ranks highly for dangerous passes, a combination of key passes and through balls. Mooy has so far averaged 0.89 key passes per 90, the third most in this dataset, and 1.78 through passes per 90, also the third most in this dataset.

The Australian has also demonstrated his ball-carrying abilities with a high rank for carries, a combination of dribbles and progressive runs. His 1.78 progressive runs per 90 are the second highest in this dataset while he has also averaged 1.25 dribbles per 90.

Defensively, Mooy stands out for his defensive duel win percentage, winning an average of 66.67 per cent. This is the fifth highest in this dataset with Reo Hatate the only other Celtic midfielder with a higher win rate (67.65 per cent).

StatsBomb’s data is also revealing when it comes to Mooy’s early domestic performances in green and white.

With similar small sample size warnings, there are a few interesting numbers that stand out here too.

Possession-wise, he unsurprisingly scores well when it comes to passing percentage, deep progressions, xG assisted and xG build-up.

Again, given Celtic’s dominance domestically, these numbers are to be expected.

They are also relatively similar to Turnbull and Hatate, the two Celtic players who have also played most of their minutes in those more advanced midfield roles.

When it comes to turnovers though, how often a player loses the ball via a miscontrol or a failed dribble, Mooy boasts the lowest of all Celtic midfielders with 1.28 per 90.

This is only slightly lower than Callum McGregor (1.30 per 90) but is significantly less than O’Riley (2.29 per 90), Hatate (2.23 per 90) and Turnbull (2.77 per 90).

Mooy also comes out on top in one key off-the-ball metric, pressure regains, the number of times a player's team win the ball back within five seconds of the player pressuring an opponent.

The Australian's 2.55 pressure regains per 90 puts him above McGregor (2.02 per 90), O’Riley (2.29 per 90), Hatate (1.56 per 90) and Turnbull (0.74 per 90).

At 32, concerns over Mooy’s ability to perform within the high-intensity system Postecoglou is seeking to transfer from domestic football to Champions League level remain valid.

Even domestically, when afforded less time on the ball, there are occasions when limitations in his game can be exposed. 

However, when he is given time in possession, Mooy’s intelligent passing game can be effective, as some of the early data here suggests. Further analysis of his data later in the season will give a clearer picture of his performances though.

With a World Cup campaign with Australia in the coming weeks that could give him a further boost, Mooy will have his part to play in the second half of the season.

He may not be a long-term solution for a Celtic midfield that will likely see several significant changes in the next few transfer windows, but he certainly has something to offer the squad in the here and now.