Since arriving in London, Antonio Conte has had one definitive wish: to sign a centre-back schooled in his homeland. In Antonio Rüdiger, to an extent, he has finally got that man. Yet, Conte would have preferred Leonardo Bonucci and there is a lingering sense that Chelsea have again had to settle for second best in this transfer window, even after winning the title so convincingly. They have stumbled over a number of targets this summer – most notably Romelu Lukaku – and the manager is unimpressed.

Rüdiger has been linked with the club for some time now but his arrival seems like a move designed to appease Conte in the short term. Chelsea needed to make a signing and, while a transfer for Monaco midfielder Tiemoué Bakayoko remains close, a deal for the Roma defender has proven more straightforward.

Conte has been keen to bolster his backline with a player who can quickly adapt to his tactical demands and, in that sense, Rüdiger should fit the bill. However, the 24-year-old Germany international is far from the finished article. After moving to Roma from Stuttgart in 2015, he took some time to adapt to a league that, from a defensive standpoint in particular, is different to any other.

While his versatility is certainly an asset, it has also held him back. He has often been asked to cover at full-back, which has restricted him from a run of games in what is clearly his strongest position. Thirteen of his 25 starts in Serie A last season came at either right or left-back, and while he is capable in both roles, Rüdiger is a centre-half.

A relatively meagre rating of 6.78 from full-back last season rose to 7.00 when he was stationed at the heart of the Roma defence, but such a modest figure shows he still has plenty of room for development. He looked more comfortable when deployed in a back three under Luciano Spalletti last season and his ability to play either side of the middle man is likely to have been key to Conte’s interest. It will offer Chelsea the opportunity to shift César Azpilicueta to a right wing-back role too, which would internally upgrade another position within the squad.

Conte’s relentless coaching has improved players such as Bonucci and, more recently, David Luiz. Rüdiger has the potential to develop in the same under Conte, but it remains an expensive risk to take on a player Chelsea don’t really need. He has the physical attributes to make a success of his time in England but his timing in the tackle is questionable: he committed as many fouls per game as he made tackles last season (both 1.7). No Roma player was penalised more often than Rüdiger, which is a rare statistic for a defender to top. He picked up seven yellow cards and one red in 26 league appearances, as well as a further dismissal in the Europa League.

Over the last two seasons, Rüdiger has committed more individual errors leading to a shot or goal than any other Roma player (six), and the third most of any outfielder in Serie A in that time. All in all, he took more time to settle in Rome than his new employers will hope to give him in London.

Rüdiger’s arrival also spells trouble for the young defenders currently at the club. Nathan Aké has has already been allowed to leave – making a £20m switch to Bournemouth – while the futures of Kurt Zouma and forgotten man Andreas Christensen - who has spent the last two seasons on loan at Borussia Mönchengladbach - have been cast into doubt. Zouma has had his injury problems in recent times but Christensen has really impressed during his time in the Bundesliga and would have hoped to make an impression at the Bridge this season. They both may have to seek opportunities on loan if they are after regular action.

The difference in quality between the three players makes Chelsea’s decision to spend £34m on Rüdiger seem curious. While Zouma spent the majority of last season on the sidelines, he started 21 Premier League matches the campaign before, with tackles per game (1.3) the only key metric in which he fared worse than Rüdiger’s (1.7) figures from the 2016-17 season. Indeed, the 22-year-old Frenchman averaged more interceptions (1.6 to 1) and clearances (5.3 to 3), and he committed considerably fewer fouls (0.4 to 1.7) and was dribbled past less often (0.3 times per game to 0.7).

Christensen also averaged fewer tackles than the new man (1.5) but at the expense of far fewer fouls (0.6), while his anticipation – 2.3 interceptions per game – and distribution are far superior to Rudiger’s. In fact, his pass accuracy of 91.5%, from 62.8 passes per game, was the third best in the Bundesliga last season, and well in excess of Rudiger’s 83.3%. The Danish international is still just 21, but he has only missed six Bundesliga matches over the past two seasons, while also picking up valuable experience in both the Champions League and Europa League.

Rudiger’s acquisition will send a message to players on the fringes at Chelsea that it will be increasingly difficult to make the breakthrough. That, of course, is no new experience for youngsters at the club. However, like David Luiz before him, the new signing has matured over the last year or so. Chelsea will hope he can follow suit and iron out the mistakes and indiscretions that, on paper, make his signature seem like the panic buy the Brazilian’s was billed as last summer – when he was signed for £34m.

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