Will Rúben Dias be the defensive rock to transform Manchester City?

Estádio do Dragão, 2 March 2019. Rúben Dias has just seen his Benfica teammate Gabriel Appelt Pires sent off in the 77th minute against Porto in a vital Primeira Liga clash.

Benfica are winning 2-1 and, having come from behind, hope to cling on. Dias is unruffled and so, as in October’s reverse fixture at Estádio da Luz when his defensive partner Cristian Lema was dismissed with the team 1-0 ahead, the 20-year-old continues a defiant, mature display that keeps Porto out, draws widespread plaudits, and ensures a victory vital in Benfica’s 37th title triumph.

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Dias signed for Manchester City for £64.3m this week and his focused, professional character has been key in his rise. He is an instinctive leader and was captain of Portugal’s Under-19s and Under-20s. The centre-half is unsmiling and cold-eyed when competing against strikers whose game he works out by studying footage to gain an edge.

Pep Guardiola’s knowledge of Dias’s driven personality helped to convince City’s manager to acquire him. The hope is the boy from Amadora is the full package who can emulate Vincent Kompany’s on-field general act while forming a bedrock partnership with Aymeric Laporte that will revamp a rearguard currently colander-like when opponents break fast or hit high balls.

Dias’s style is more abrasive than Kompany’s. He has received only one red card but an aggression that can spill into the red zone drew 12 bookings last term and is the prism through which he is viewed in Portugal. Doubters, though, were proved wrong following that sending off, which came in Benfica’s 3-2 Champions League win at AEK Athens on the stroke of half-time (a second yellow card) in October 2018 and stoked the debate regarding his perceived penchant for “shithousery”.

The riposte was telling as Dias returned with the performance in the win at Porto in which Lema was sent off and he was voted man of the match.

Still, there are questions regarding his pace and ability to succeed at the elite level where City aim to dominate. The 6ft 2in Dias is not slow but nor is he considered fleet-footed. And there is a school of thought that he was not the most prized defensive talent to emerge recently from Benfica’s academy. Francisco Ferro is nominated by some for that status but Dias’s team-first, die-for-the-cause ethos made him the go-to at the club for Rui Vitória, then Vitória’s successors as head coach, Bruno Lage, Nélson Veríssimo and Jorge Jesus.

Guardiola will hope to harness this as he rebuilds a side missing Kompany and David Silva; that have a 32-year-old Sergio Agüero and 35-year-old Fernandinho as still key; and that have an issue at left-back where Benjamin Mendy’s City career resembles Luke Shaw’s at Manchester United: unfortunate serious injury apparently blunting the pace and verve that made each stand-out talents.

Dias has his own connection with City’s crosstown rivals in Victor Lindelöf, the centre-back he featured with seven times for Benfica B and a player three years his senior who moved to United in summer 2017. The Swede is being scrutinised for unconvincing displays for Ole Gunnar Solskjær’s team, and the good news for City from Portugal is that Dias is considered the finer defender.

Before him is the challenge of showing this and adapting to a breathless domestic game. City have poor form regarding the recruitment of a costly centre-back from Portuguese football. In August 2014 Eliaquim Mangala was signed for £42m from Porto and proceeded to disappoint. Yet Dias gives himself every chance of success by arriving as an accomplished English speaker due, in part, to his girlfriend, Mariana Gonçalves, who as the iTunes chart-topper April Ivy sings solely in the language.

Up for debate is whether Dias was Guardiola’s first, second or even third choice. Privately the club’s stance is that Kalidou Koulibaly was never the No 1 target despite their pursuit of the 29-year-old – though when Dias joined a screenshot of the City website was circulated that showed fans being asked to pose questions to the Napoli man. More certain is that Koulibaly, Atlético Madrid’s José Giménez, and Sevilla’s Jules Koundé were of interest. Just as certain is that what matters now is how Dias performs.

He will aim to seize an opportunity that might not have been possible if Benfica had not been unexpectedly eliminated from the Champions League by PAOK last month. This meant the club had to sell to cover projected finances lost from not being in the competition, and with Nicolás Otamendi going the other way for £13m, this was a deal that worked for all parties.

Dias has 19 caps and was man of match in last summer’s Nations League final. He could feature in the visit to Leeds United on Saturday. Either way the serious business is about to begin.