Dias becomes just the latest in a string of expensive defensive signings, totalling over 450m euros, since Guardiola was appointed in 2016
Manchester City announced the signing of Portuguese international centre-back Ruben Dias on a six-year deal from Benfica Tuesday in the hope of solving the defensive problems that have dogged Pep Guardiola's side over the past year.
Benfica Sunday confirmed they had reached an agreement to sell 23-year old Dias for 68m euros (£62m, $79m) plus an extra 3.6m euros in potential bonuses, with Nicolas Otamendi heading in the opposite direction for 15m euros.
Benfica coach Jorge Jesus said at the weekend that selling Dias was necessary for the club to balance their accounts after a defeat by Greek side PAOK in the third qualifying round of the Champions League ended their hope of reaching the group stage.
Dias becomes City's third signing of the summer after center-back Nathan Ake from Bournemouth and Spanish winger Ferran Torres from Valencia.
The need for more defensive reinforcements was evident as City were thrashed 5-2 at home to Leicester Sunday - the first time a Guardiola side has ever conceded five in his distinguished managerial career.
However, Dias becomes just the latest in a string of expensive defensive signings, totalling over 450m euros, since Guardiola was appointed in 2016.
Despite huge price tags, John Stones, Joao Cancelo and Benjamin Mendy are not first-team regulars, while Ake has been signed as back-up to Aymeric Laporte.
Otamendi, 32, won several major honors during his time at the Etihad, including two Premier League titles, and made more than 200 appearances in all competitions in five seasons.
The Argentine international has previously played in Portugal, turning out for Benfica's bitter rival Porto between 2010 and 2014.