Selling Nathan Aké would create a problem Pep Guardiola solved at Man City in 2020

Back in late 2020, Manchester City had a real problem in central defence - they were leaking goals at an alarming rate.

After meekly surrendering their Premier League title to Liverpool the year prior, there was massive pressure on Pep Guardiola to bounce back and compete for the title in a bizarre behind closed doors season.

They started the campaign with a concerning 5-2 defeat to Leicester City at the Etihad Stadium, where a back four of Benjamin Mendy, Eric Garcia, Nathan Aké and Kyle Walker conceded three penalties across the 90 minutes.

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It was an issue all too familiar for City fans, who had already seen Fernandinho and Rodri stand in as emergency centre-backs in the 2019/20 season after big injuries to John Stones and Aymeric Laporte.

City were clearly light in that area, and weeks later, Ruben Dias joined Aké as the club's major summer signing. There was a lot of pressure on the Portuguese international's shoulders after his £65 million transfer, but he certainly rose to the challenge and won FWA Footballer of the Season in his debut campaign.

Since his move, the quartet of Dias, Laporte, Stones and Aké have powered City to consecutive Premier League titles, one Carabao Cup and a club-first Champions League final appearance. It's perhaps the most settled a City backline has been in years - and Guardiola has the perfect balance.

Two left footers and two right footers is every manager's dream. Guardiola has been able to rotate between four world-class options for two years, but movement in the transfer window could threaten that luxury next season.

Aké - who was a youth player at Stamford Bridge - is on Chelsea's radar this summer, as Thomas Tuchel looks to