Liam Scales completed a remarkable Celtic career turnaround by signing a new four-year deal with the club last week.

Seemingly destined to leave last summer after spending the 2022/23 campaign on loan at Aberdeen, Scales has defied expectations to become a mainstay in the starting eleven. The Republic of Ireland international took the opportunity that arose at the start of the season when Celtic were dealt a series of injury blows at centre-back and went on to establish himself as first-choice, making 41 appearances in all competitions to date.

Summer signings Maik Nawrocki and Gustaf Lagerbielke have had to play back-up to Scales while Stephen Welsh has also been preferred to Nawrocki and Lagerbielke at points. Close to an exit in January, Lagerbielke, a ÂŁ3m signing from Elfsborg, seems certain to leave less than 12 months after making the move from Sweden to Scotland. Question marks remain over Nawrocki too who has endured an injury-hit first season following a ÂŁ4.3m move from Legia Warsaw. Brendan Rodgers will still have Welsh to call on next season, the academy graduate signing a new deal through to 2028 last summer, but another back-up at centre-back, Yuki Kobayashi, is another whose future surely lies away from Celtic Park.

Since Rodgers might find himself a couple down on his current batch of centre-backs, he may look to the transfer market this summer for a new option. This addition would hopefully be of a level, at the very least, to provide a serious challenge to Scales for the position next to Celtic's top centre-back, Cameron Carter-Vickers. Here, as we have done for previous positions lately such as left-back, central midfield and striker, we identify three centre-back candidates that the club could target this summer, should Rodgers look to further reinforce the heart of his defence.

As with the other positions, the approach for this is data-led and within the club’s recent model. Each player suggested 26 years old or younger (we have upped the age bracket given the manager’s recent comments about looking to add more experience) and currently playing in leagues that the club would likely be scouting extensively.

There are also some profile traits that we are looking to identify, ones that are key for a Celtic centre-back. Given how much of the ball Celtic’s centre-backs have each game, effectiveness in possession will be a primary consideration. Defensive robustness, to deal with the physical nature of the Scottish Premiership, will of course also be important while experience of playing on the left of a centre-back pairing will also be a consideration.

Derek Cornelius – Malmo

The first candidate is Derek Cornelius. An international teammate of Alistair Johnston, Cornelius is currently plying his trade in the Swedish Allsvenskan with Malmo. A natural left-footer like Scales, the 26-year-old joined Malmo ahead of the 2023 Allsvenskan from Greek side Panetolikos.

Cornelius, who has also had spells in Germany and Serbia, and back in his native Canada with Vancouver Whitecaps in MLS, enjoyed an excellent first season in Swedish football as Malmo ended the season as champions.

The 6’ 2” defender would be more than comfortable in Celtic’s possession-dominant system, given Malmo have adopted a similar approach in Sweden – they averaged just over 60 per cent of the ball in the 2023 Allsvenskan, more than any other team in the league.

His percentile rank chart, which compares Cornelius to his positional peers in last year’s Allsvenskan, sees him rank highly for general passes (65.65 per 90) and forward passes (24.51 per 90). This is of course to be expected given Malmo's ball dominance. His accuracy percentages for both of these types of passes are impressive with Cornelius completing 92.87 per cent of his general passes and 86.36 per cent of his forward passes.

His ranks for longer, more ambitious passes (long passes and progressive passes) are not as high in volume and accuracy. This, coupled with his general passing and forward passing numbers, suggests he is comfortable moving the ball around the back and into the base of midfield during the initial phases of build-up but may not be suited to being overly ambitious with his passing.

His attacking section shows he was a bit of a threat in the opposition box with his 0.12 goals per 90, from 0.14 xG per 90, ranking in the 93rd percentile. His attacking section also shows a high rank for dribbles, again likely due to being on the ball more than most other players in his position in the league. However, his dribble success rate and volume of progressive runs (0.31 per 90) rank below the 50th percentile.

Cornelius’ ability to read the game stands out in his defensive section with the Canadian making 7.96 possession-adjusted (PAdj) interceptions per 90 last year, amongst the most on average of any Allsvenskan centre-back in 2023. His 1.22 fouls per 90 is towards the higher end for an Allsvenskan central defender and although his defensive duels win percentage (64.42 per cent) only ranks just above the bottom quartile too, Cornelius’ aerial duel win percentage is comfortably above average (60.5 per cent).

Encouragingly, his numbers for these duels are also up in the early part of the 2024 edition of the Swedish Top Flight, which kicked off in late March – 81.58 per cent for defensive duels and 74.07 per cent for aerial duels.

Reportedly attracting serious interest from Dutch clubs Ajax and Feyenoord, Celtic would potentially have to move fast if they wanted to secure Cornelius’ services. With a market value of just over £2m, even with interest from others, he is unlikely to be outwith the club’s budget.

Dennis Hadzikadunic – Hamburg (on loan from Rostov)

The next potential option is 25-year-old Bosnia-Herzegovina international Dennis Hadzikadunic. Currently on loan with Hamburg in the Bundesliga 2 from Russian side Rostov, 6’ 3” Hadzikadunic came through the ranks at his local side Malmo and represented Sweden up to under-21 level before declaring for Bosnia in 2020.

He joined Rostov in 2018 and made 69 appearances for the Russian Premier League side before a loan back with Malmo, as well as a short spell in La Liga with Real Mallorca.

Unlike Cornelius, Hadzikadunic is a natural right footer but has spent most of his season on loan in Germany’s second tier on the left side of their favoured 4-3-3, making 23 appearances for the promotion chasers who currently sit fourth.

Taking his attacking section first, Hadzikadunic has not been as big a goal threat in this season’s Bundesliga 2 as Cornelius was in last year’s Allsvenskan (0.04 goals per 90). The Bosnian stands out as a more progressive ball carrier though (1.29 progressive runs per 90. Like Cornelius, Hadzikadunic has been used to, this season anyway, playing in a ball-dominant side – Hamburg have averaged 55.87 per cent of the ball in the league this season.

Another that would likely be comfortable in a possession-heavy system like Celtic’s, Hadzikadunic has a more rounded possession profile. Most importantly here though, his forward passing accuracy rate (81.65 per cent) is in the top quartile while he has also attempted an above-average, for a Bundesliga 2 centre-back, number of progressive passes (8.42 per 90). He also boasts an above-average accuracy percentage in these passes (73.33 per cent). 

In the defensive section, Hadzikadunic is not involved in a huge amount of defensive duels, compared to his positional peers, and does not rank too favourably for his win percentage in these types of duels (63.73 per cent). He only just ranks above the bottom quartile for his PAdj interceptions too and, like Cornelius, has an above-average rank for his foul rate. His aerial duels win rate (64.66 per cent) does stand out though, impressively amongst the highest for a Bundesliga 2 centre-back this season.

Reportedly on the radar of Juventus last year, Hadzikadunic is highly likely to be on the move again this summer, whether that be another loan or a permanent move aware from Rostov. He still has two years to run on his contract with the Russians but is valued around a similar price bracket to Cornelius so is another who would hopefully be a realistic target.

Harold Moukoudi – AEK Athens

The final possible option is Harold Moukoudi, who is currently playing in the Greek top flight with AEK Athens.

The 6’ 3” Cameroon international already has some experience in British football following a loan spell with Middlesbrough in 2020. Before then he spent his career in France with Le Harve and St Etienne.

Like Hadzikadunic, Moukoudi is naturally right-footed, and although he has not spent as much time on the left side of the centre-back pairing this season, he does still have experience there.

Due to a call-up for the African Cup of Nations and a recent muscle injury, Moukoudi has not played a huge amount of minutes for the Greek champions in the league this season, hence the lower minute count for his percentile rank chart. Although this should be considered when analysing his numbers, we can still see the 26-year-old standing out in some of the key areas we are looking for.

Possession-wise, Moukoudi is, like our other two options, used to playing in a ball-dominant side – AEK are averaging 58.64 per cent of the ball this season. This is reflected in his chart, ranking in the top quartile for his overall pass volume (51.56 per 90).

Again, more important are the accuracy percentages and here we can see Moukoudi’s overall passing accuracy (92.82 per cent) and forward passing accuracy (86.06 per cent) are amongst the very best for a centre-back in the Greek Super League. Although he does not attempt a huge number of progressive passes (6.11 per 90), again, his accuracy rate (75.41 per cent) is very good, in the 80th percentile when compared to his positional peers.

Accomplished in possession, Moukoudi, albeit in a smaller sample size, boasts more impressive ranks for his duel win percentages than Cornelius and Hadzikadunic. His defensive duel win percentage (80.3 per cent) is unmatched amongst players in his position in the league and his aerial duel win percentage (64.29 per cent) ranks in the top quartile. Not as progressive through carries as Hadzikadunic, Moukoudi’s 0.1 goals per 90’s ranks highly versus his positional peers.

Interestingly said to have been a target in Rodgers’ first spell, Moukoudi would likely be ready-made to slot into the heart of Celtic’s defence. With two years left on his contract at AEK and valued at over £4m, he may command the highest fee of the three options highlighted here though.