Benfica's Ruben Dias is a defender under consideration by Manchester City ahead of the summer transfer window, with Pep Guardiola making defensive reinforcements a 'priority'.
Reigning champions City are all but certain to finish 2019/20 in second after failing to keep pace with runaway leaders Liverpool.
While the Citizens boast a league-high 71 goals scored, they have only the fourth-best defensive record and have lost seven times so far this season.
Serious injury to Aymeric Laporte in September left Guardiola short on quality options at centre back, especially after club-captain Vincent Kompany departed last summer.
Nicolas Otamendi and John Stones have often flattered to deceive in the role, while 35-year-old Fernandinho has been used as a stand-in defender for most of the campaign.
The Evening Standard reports that Guardiola is 'regretting' City's failure to sign Harry Maguire from Leicester last summer and a new centre back to partner a fit-again Laporte is the 'priority' in the upcoming window.
The report names 23-year-old Benfica star Dias as a player City have 'watched' but don't name a price tag or the extent of the Premier League side's interest.
A previous target of Barcelona, Dias has a contract in Lisbon until 2024 and a buyout clause of £87m, meaning he will not be cheap.
While that figure may not seem like a serious deterrent to a club of City's means, it is worth noting the Citizens famously opted not to pay £80m for Maguire, who ended up at rivals United.
Dias is a 17-cap Portugal international who was part of the inaugural Nations League-winning side in 2019. He also won the Primeira Liga with Benfica the same year.
In addition to Dias, 90min reported last month that City were interested in former Guardiola player David Alaba, who could even be used as an exchange option in a deal to finally take Leroy Sane to Bayern Munich.
Real Madrid, Barcelona and several other clubs have also been linked with the 27-year-old Austrian, who is one of football's most versatile operators, having spent much of the 2019/20 campaign at centre back.