Rating Man City's potential centre-back targets: Koulibaly, Soyuncu, Ajer

Editor's note: Tor-Kristian Karlsen is a Norwegian football scout and executive and is the former chief executive and sporting director at AS Monaco. He will write regularly for ESPN on the business of soccer and the process of scouting. In his latest column, he identifies five potential centre-backs Man City could target in the transfer window to pair alongside Aymeric Laporte.

Despite spending unimaginable amounts on their squad over the past decade, Manchester City still find themselves short of convincing centre-back options. Since Vincent Kompany left for boyhood club Anderlecht last summer, the club has also lacked leadership from the back. And whereas their defensive record isn't in itself bad -- 33 goals conceded in 31 games is the fifth-best mark in the Premier League -- and defending is as much about organisation and working as a unit as individual players, it still feels like City are one quality reinforcement away from regaining defensive solidity and reliability.

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With Aymeric Laporte slowly being reintroduced to first-team duty following almost a year out through injury, Pep Guardiola will be hoping to have his top defender at full fitness in time for the start of next season. But, while having the Frenchman back will come as a relief, there's still an open spot to be filled next to Laporte. As much as Fernandinho has done an honest job deputising in defence, neither the Brazilian, Nicolas Otamendi nor John Stones appear to be the long-term solution to Manchester City's defensive puzzle. City also added former Chelsea product and Bournemouth defender Nathan Ake last week, but he feels like a transfer to bolster depth than slot directly into the first team.

As one of the most independent-minded, lateral-thinking football coaches there is, it's hard to predict Pep Guardiola's next move but nevertheless, I've identified five right-footed candidates -- each with their own plusses and minuses -- who could possibly be the ideal foil for the left-footed Laporte in the centre of the City's defence.

The no-brainer: Kalidou Koulibaly, Napoli (Age 29)

Kalidou Koulibaly is of the few centre-backs plying his trade outside the traditional 8-10 elite clubs in Europe who would comfortably settle in quite seamlessly at the top of the Premier League -- or La Liga or the German Bundesliga, for that matter. At first glance, his imposing frame and stature are his most striking features, but when the game settles down, it doesn't take long to notice that the France-born Senegal international is more than pace and power -- he's also good on the ball and stylish with it. Having already stood out as one of the top defenders in Serie A for a number of years, Koulibaly would have no issues in coping with the intensity of the Premier League, confidentially passing his way out of opponent's high-pressing game or generally responding to Pep Guardiola's high demands.

More to the point, Koulibaly -- as opposed to many of the easy on the eye centre-backs at the high level of the game -- is also an efficient, no-nonsense defender. It's no secret that the 29-year-old has been closely monitored by Premier League clubs the last few years, with City's arch-rivals Manchester United and Liverpool said to be interested. He won't come cheap though, as Napoli President Aurelio De Laurentiis, has made it clear that only a "ridiculous offer" in the region of €100 million would make him even contemplate the prospect of selling the defender. As much as Koulibaly clearly has the required level to improve Manchester City defensively, it remains to be seen whether anyone is willing to spend such amounts for a player with practically no resale value during what is likely to be a summer of austerity in the transfer market.

The breakout candidate: Caglar Soyuncu, Leicester City (Age 24)

After scarcely featuring during his first season at Leicester following his €21 million move from Freiburg in the summer of 2018, Caglar Soyuncu has now established himself as one of the most impressive centre-backs in the Premier League. Any worries about Leicester being significantly weakened defensively following the sale of Harry Maguire to Manchester United were soon forgotten as Brendan Rodgers' team were looking even more solid and compact -- with only Liverpool having a more impressive defensive record until the final four rounds of the league season, from which Leicester conceeded a total nine goals (Soyuncu wrapped up his season with being sent off in the 4-1 loss at Bournemouth with three games still to be played).

The Turkish international stands out with his aggressive and "proactive" style of defending -- he times and anticipates his interceptions well, never afraid of stepping out of the defensive line to snap up the ball in front of an opposing forward. His mobility and ability on the ball encourages him to carry out a rather high-risk type of defending -- never afraid of pulling off a dribble to get himself out of trouble or ease the pressure -- which, as yet, hasn't proved costly for Leicester City. He's also excellent at timing his aerial challenges. All those stand-out qualities would be compatible with Manchester City's way of playing football and make Soyuncu an interesting proposition. It's probably just a matter of time before the Foxes face another fight to hang on to a highly-rated centre-back.

The atypical choice: Jose Maria Gimenez, Atletico Madrid (Age 25)

For all his principles, Pep Guardiola does occasionally like to go against the grain and surprise people -- so what if he suddenly relaxed -- not abandoned -- his ideas of rigidly having his centre-backs play out from the back? The Uruguayan is among the best out-and-out defenders in European football; whether throwing his body on the line to save the ball from going in or tussling all night with the most powerful centre-forwards in the game.

Very much the archetypical Uruguayan defender, his game is mostly about winning challenges and less about passing and building from the back. That's not to say that that he's completely useless with the ball; after all, he holds his own in a strong Atletico Madrid side. His impressive aerial game and man-marking qualities could be useful for a side that's still prone to conceding soft goals. Unfortunately, injuries have so far prevented the 25-year-old from pushing on to an even higher level.

The 'Steady Eddie': Matthias Ginter, Borussia Monchengladbach (Age 26)

Previously a utility player -- often used at right-back and as a holding man in midfield -- the German international has now appeared to permanently settle into the centre-back role for both club and country. Predominantly a solid, dependable and understated player on the pitch -- though often heralded by his teammates for his "quiet leadership" -- Ginter has recently been given more licence to break forward from his defensive role and has also developed his passing game.

With both Niklas Sule and Antonio Rudiger struggling with long-term injuries, Ginter has claimed a starting place in the Germany team and has received accolades from Joachim Low for his selfless, loyal approach as a "team before individual" kind of guy. The calm, intelligent defender -- who hardly ever picks up bookings and has yet to be sent off in his professional career -- is arguably the best performing centre-back in the Bundesliga this season. The 26-year-old, who played under Jurgen Klopp at Borussia Dortmund, would have no problems mastering Manchester City's passing style, though he would need to become even more assertive in his marking game.

The outsider: Kristoffer Ajer. Celtic (Age 22)

Perhaps a transfer to Manchester City comes one move too early in the career of the Norwegian centre-back, yet he does possess some qualities which will surely have caught the eye of City. Originally a defensive midfielder, Ajer is comfortable with the ball at his feet and can often be seen surging forward -- at times possibly even too adventurously -- from the heart of the Celtic defence. His ability to help build from the back and push forward to create numerical advantages further up the pitch are skills that strongly match the way Pep Guardiola ideally likes to play the game.

Standing six-foot-five -- and not particularly slow on the turn -- Ajer has had few problems holding his own in the air, while four seasons in the Scottish game have also given him the aggressive edge that is often needed to survive in the Premier League. Though the Norway international (14 caps) is still relatively unproven at the highest level, he's dealt well with every challenge thrown at him since arriving at Celtic in 2016 and is a determined professional and a natural leader. While Ajer could be seen as a riskier, albeit lower-cost investment at this early stage in his career, it's worth noting that he's at a strikingly similar point -- both in terms of career and development -- to where Kompany was when he joined Manchester City in 2008...