Bukayo Saka and Ezri Konsa teamed up with England at the World Cup - and are set to do so again at Arsenal.

Arsenal are not standing still as they look to defend their Premier League title. The Gunners have spent more than £100m already, bringing in Bruno Guimaraes from Newcastle (£75m) and Club Brugge winger Christos Tzolis (£34m) during this transfer window. And they are now set to bring in Ezri Konsa from Aston Villa for around £51m.

It may seem strange that Arsenal - who have seven senior defenders - want to bring in another established centre-back, but there are reasons why Mikel Arteta has decided to go for the England international.

Last season, Arsenal's extremely well drilled backline, aided by the effective partnership of William Saliba and Gabriel Magalhaes, helped them win their first title in 22 years. They only conceded 27 league goals. But half of their title-winning defence is not going to be fit for the first part of the season. Saliba has been ruled out for an 'extended period' with a long-term back issue which he had been managing last season and which ended his World Cup with France early. Jurrien Timber, Arsenal's first-choice right-back, is also out for the opening weeks of the season with a groin problem that caused him to pull out of the Netherlands World Cup squad.

That leaves Ben White, who has had his own fitness issues in recent seasons, as Arsenal's only fit right-back and 21-year-old Cristhian Mosquera as the only right-sided centre-back to partner Gabriel Magalhaes. It could be argued that Arsenal, who also made defender Piero Hincapie's loan deal permanent this summer, could be able to cope without signing another defender. But Arteta does not seem to like fielding two left-footed players at centre-back - which would happen if White got injured and Mosquera had to move to right-back.

Riccardo Calafiori is preferred at left-back by Arteta, because of the unpredictability he brings to the Arsenal attack. Hincapie is left-sided too. Highly rated 16-year-old academy defender Marli Salmon is also on the books but is most likely to be used sparingly in cup competitions as he continues to develop.

Before Arsenal moved for Konsa, they considered signing Bayer Leverkusen defender Jarell Quansah who can play at right-back and as a right-sided centre-back. Konsa, like Guimaraes, is 28 and in the prime of his career. A seasoned international centre-back, he lifted the Europa League with Villa last season. He is one of his country's most reliable performers, starting seven of England's eight games at the World Cup.

His Premier League numbers show why Arsenal were so keen to bring Konsa in. He was ranked as having the best ground duel success (73.1%) and best passing accuracy (95%) of all defenders in the Premier League last season. His passing accuracy was the best of any player too, while he was also ranked first out of all Premier League outfield players to contest more than 20 ground duels in the league last season. He also ranked fifth of all defenders in the league for ball carries of more than five metres - and he carried his passing accuracy into the World Cup, as in his seven starts, he registered a 97% pass completion rate.

Many Arsenal fans are wondering if Konsa will play regularly when Saliba and Gabriel are fit. Arteta's first-choice backline of Timber, Saliba, Gabriel and Calafiori appears hard to break into, on paper. But the Gunners played 63 games in all competitions as they won the title, reached the final of the Champions League, the final of the Carabao Cup and the quarter-final of the FA Cup.

Arsenal were plagued by injuries during the campaign and Arteta is trying to avoid those issues this time. In the aftermath of the Champions League final, Arteta was quick to say that the Gunners need to be "very ambitious, very fast, and very smart" to build on their Premier League win. Arsenal spent £250m last summer. The arrival of Konsa will take this summer's outlay to over £150m.

Arteta has some of the best depth of quality in Europe to call on, in a squad worth £1.19bn according to Transfermarkt.

When asked about the perfect number of players in his squad, Arteta said there are variables he takes into account. "It depends on the ability and the history of those players," Arteta said. "I think there is a lot of factors that count. Twenty-two outfield players and three goalkeepers of what is enough, or maybe you know more. You need to understand what happened in the previous season, the injury record of those players, the versatility of certain players. But I'm sure we're going to hit the right number to have a bit of both a lot of competition with the right level of cooperation in the team and everybody feeling important."

Arsenal want to be one of the global powerhouses in world football. Chief executive Richard Garlick said in an interview with the Times that joining the world's superclubs is "the goal - that's the ambition". The Gunners are actively exploring how to increase their revenue off the pitch and are looking at stadium expansion plans. Garlick, in an interview with BBC Sport, acknowledged that the "pool of players is smaller now than it was a few years ago if we're going to improve". In other words, as Arsenal have got better, it has become more difficult to find players who will improve them.

They are still in the market for a forward and have a long-term interest in Julian Alvarez. They have also monitored 21-year-old forward Kenan Yildiz from Juventus. But after Konsa's arrival, if another player does come in, expect the signing to lift club to another level.

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